INTERNATIONAL TREE NUT COUNCIL

NUTRITION RESEARCH & EDUCATION FOUNDATION

LISTING OF TREE NUT RESEARCH REFERENCES

(Last updated 05-11-06)

REFERENCE LINK INDEX

A.     CANCER AND ANTIOXIDANT ACTIVITY
B.     CARDIOVASCULAR
C.     DIABETES
D.     GALLSTONES
E.     GENERAL
F.     MENARCHE
G.     WEIGHT CONTROL
H.     NUTRIENT COMPOSITION

MIXED TREE NUT REFERENCES

CANCER AND ANTIOXIDANT ACTIVITY

American Institute for Cancer Research, 1997. World Cancer Research Fund. Food, Nutrition and the Prevention of Cancer: A Global Perspective. Nuts and Seeds. 450-1

Since the early ‘80s, a number of expert reports have reviewed the literature on diet and cancer and made recommendations designed to reduce the risk of cancer. The report, of which this is a summary, builds on that earlier work. The experts recommend that populations consume nutritionally adequate and varied diets, based primarily on foods of plant origin. They specifically recommend that the public choose predominantly plant-based diets rich in a variety of vegetables and fruits, legumes and minimally processed starchy staple foods.The report notes, “While there are as yet no useful epidemiological data on nuts and seeds, it is biologically plausible that diets high in specific nuts and seeds or these foods as a whole, protect against cancers.”

Bruce, B., G.A. Spiller, L.M. Klevay, S.K. Gallagher, 2000. A diet high in whole and unrefined foods favorably alters lipids, antioxidant defenses and colon function. J Clin Nutr. 19(1): 61-7.

Diets rich in whole and unrefined foods such as nuts, contain high amounts of antioxidant phenolics, fibers and numerous other phytochemicals that may be protective against chronic diseases.This study compared the effects of a phytochemical-rich diet to a refined-food diet on lipoproteins, antioxidant defenses and colon function.Twelve hyperlipidemic women followed 2 diets for 4 weeks starting with a refined-food diet, and then crossing over directly to the phytochemical-rich diet.Fasting serum lipids and antioxidant enzymes were measured at the end of each period.The results showed that total calories and fat intake were similar in both diet periods, but saturated fat decreased by 61%, total cholesterol by 13% and LDL by 16% in the phytochemical-rich diet group. Dietary fiber, vitamin E, vitamin C and carotene intakes were 160%, 145%, 160% and 500% more, respectively, than during the refined-food diet period.In conclusion, a diet high in phytochemical-rich foods positively affected lipoproteins, decreased the need for oxidative defense mechanisms and improved colon function.

Hebert, J.R., T.G. Hurley, B.C. Olendzki, J. Teas, Y. Ma, J.S. Ha, 1998. Nutritional and socioeconomic factors in relation to prostate cancer mortality: a cross-national study. J Natl Cancer Inst. 90:1637-47.

This study included data for men ages 45-74 years from 59 countries.As the consumption of nuts and oilseeds increased, prostate cancer mortality decreased.

Jain, M.G., G.T. Hislop, G.R. Howe, P. Ghadirian, 1999. Plant foods, antioxidants and prostate cancer risk: findings from case-control studies in Canada. Nutr and Cancer. 34(2):173-84.

This study, which looked at data from three case-control studies involving 1,253 subjects followed for five years, revealed a decreased risk for prostate cancer with an increased intake of beans/lentils/nuts.The inverse effect of the latter may be due to their phytoestrogen content.

Jenab, M., et al., 2004. Association of nut and seed intake with colorectal cancer risk in the European prospective investigation into cancer and nutrition. Cancer Epidemiol Biomarkers Prev. 13(10):1595-603.

This study looked at the effect of nut and seed intake on colorectal cancer in men and women. Total nut intake was determined from country-specific dietary questionnaires for 855 (327 men, 528 women) colon cancer cases, 474 (215 men, 259 women) rectal cancer cases, and 478,040 (141,988 men, 336,052 women) total subjects.Division of the data into colon and rectal cancers showed a significant protective effect of nut intake on colon cancer in females at the highest quintile of intake, which was greater than six grams daily. The results showed a significant protective effect of increased nut intake on colon cancer in women, with no effects on rectal cancer for either gender.

Kune, S., G.A. Kune, L.F. Watson, 1987. Case-control study of dietary etiological factors: the Melbourne colorectal cancer study. Nutr Cancer. 9:21-42.

This study compared 715 cases with 727 age- and sex-matched community controls.The combination of a high-fiber and high-vegetable intake was found to be protective against large bowel cancer as well as colon and rectal cancers. Pulses, nuts and seeds were one of the groups analyzed and shown to have possible protective effects.

Mills, P.K., W.L. Beeson, R.L. Phillips, G.E. Fraser, 1989. Cohort study of diet, lifestyle, and prostate cancer in Adventist men. Cancer. 64:598-604.

In a 6-year prospective study researchers looked at the effect of diet and lifestyle on the incidence of prostate cancer in a cohort of approximately 14,000 Seventh-day Adventist men. Strong protective relationships were seen with increasing consumption of dried beans, lentils, fresh citrus fruit, raisins, dates and other dried fruit, nuts and tomatoes.

Pickle, L.W., M.H. Greene, R.G. Ziegler, A. Toledo, R. Hoover, H.T. Lynch, J.F. Fraumeni, Jr., 1984. Colorectal cancer in rural Nebraska. Cancer Research. 44:363-9.

A case-control interview study of colorectal cancer was conducted in eastern Nebraska to determine reasons for the elevated colon cancer mortality rates during 1950 to 1969. Information provided by 86 colorectal cancer cases was compared to 176 matched controls.The data suggest ancestry and certain dietary patterns may be associated with the colon cancer in this region.Nuts and legumes were associated with a lower incidence of colon cancer.

Singh, P.N., G.E. Fraser, 1998. Dietary risk factors for colon cancer in a low-risk population. Am J Epidemiol. 148:761-74.

In a 6-year prospective study, researchers looked at the relation between diet and incidence of colon cancer in 32,051 non-Hispanic white cohort members of the Adventist Health Study who, at baseline, had no documented or reported history of cancer. Those who ate nuts more than 4 times per week had a lower incidence of colon cancer than those who never ate nuts or ate them 1-4 times per week.

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CARDIOVASCULAR

Abbey, M., M. Noakes, G.B. Belling, P.J. Nestel, 1994. Partial replacement of saturated fatty acids with almonds or walnuts lowers total plasma cholesterol and low-density-lipoprotein cholesterol. Am J Clin Nutr. 59:995-9.

This study involved 16 normolipidemic men in a consecutive, supplemental field study that lasted for three, 3-week dietary periods.During the first three weeks, subjects consumed a reference diet that included a background diet supplemented with 50g/day of peanuts, 40g/day of coconut, and 50g/day of a coconut confectionary bar.During the second three weeks, subjects consumed the background diet supplemented with almonds (84g/day) and during weeks 7-9, subjects consumed the background diet supplemented with walnuts (68g/day).The almond diet lowered total cholesterol by 7% and LDL by 10%, while the walnut diet lowered total cholesterol by 5% and LDL by 9%.Neither diet had a significant effect on HDL or triglycerides.

Albert, C.M., M. Gaziano, W.C. Willett, J.E. Manson,2002. Nut consumption and decreased risk of sudden cardiac death in the Physicians’ Health Study. Arch. Intern. Med. 162:1382.

This study, with 21,454 male participants enrolled in US Physicians’ Health Study, prospectively assessed whether increased frequency of nut consumption, as ascertained by an abbreviated food frequency questionnaire at 12 months of follow-up, was associated with a lower risk of sudden cardiac death and other coronary heart disease end points.Compared with men who rarely or never consumed nuts, those who consumed nuts 2 or more times per week had a 47 percent lower risk of sudden cardiac death and a 30 percent lower risk of total coronary heart disease death.

Appel, L.J., et al., 1997. A clinical trial of the effects of dietary patterns on blood pressure. NEJM. 336:1117-24.

In this study, Dietary Approaches to Stop Hypertension (DASH), researchers looked at the effects of dietary patterns on blood pressure in 459 adults with systolic blood pressures less than 160 mm Hg and diastolic blood pressures of 80 to 95 mm Hg.For three weeks subjects were fed a control diet that was low in fruits, vegetables and dairy products, with a fat content typical of the average US diet.They were then randomly assigned to receive the control diet, a diet rich in fruits and vegetables, or a “combination” diet rich in fruits, vegetables and low-fat dairy products and with reduced saturated fat and total fat. Sodium intake and body weight were maintained at constant levels.The results showed that a “combination” diet rich in fruits, vegetables and low-fat dairy foods, and with reduced total and saturated fat can significantly lower blood pressure.

One and one-half ounces of nuts, or 1/3 cup, are recommended 4-5 times per week (as part of the nuts, seeds and legumes group) in the DASH eating plan, primarily due to the fact that they are rich sources of energy, magnesium, potassium, protein and fiber.

Berry, E.M., S. Eisenberg, Y. Friedlander, D. Haratz, N.A. Kaufmann, Y. Norman, Y. Stein, 1992. Effects of diets rich in monounsaturated fatty acids on plasma lipoproteins – the Jerusalem Nutrition Study. II monounsaturated fatty acids vs. carbohydrates. Am J Clin Nutr. 56:394-403.

Seventeen male students were randomly assigned to a crossover study with two 12-week dietary periods of monounsaturated fatty acids (MUFA) versus a carbohydrate (CHO)-rich diet, while polyunsaturated (PUFA) and saturated fatty acids (SFA) were kept similar. (Nuts are rich in MUFAs and PUFAs).

Berry, E.M., S. Eisenberg, D. Haratz, Y. Friedlander, Y. Norman, N.A. Kaufmann, Y. Stein, 1991. Effects of diets rich in monounsaturated fatty acids on plasma lipoproteins – the Jerusalem Nutrition Study: high MUFAs vs. high PUFAs. Am J Clin Nutr. 53:899-907.

The Jerusalem Nutrition Study was a randomized, controlled crossover study involving 18 young men that examined the effects of a high mono-unsaturated fat (MUFA) diet (including almonds, olive oil and avocado) versus a high polyunsaturated fat (PUFA) diet (including walnuts, safflower and soy oils) during two 12-week dietary periods.The MUFA diet lowered total cholesterol by approximately 10% and LDL by 14% compared to baseline values, while the PUFA diet lowered total cholesterol by 16% and LDL by 21%.There were no significant effects on HDL or triglycerides.

Bruce, B., G.A. Spiller, 1997. Nuts and healthy diets. Veg Nutr: An Int J. 1(1):12-16.

Since ancient times, nuts and seeds have been considered healthful foods worldwide.This paper looks at the history and composition of a variety of nuts, and their effects on health, particularly heart disease.According to the authors, “nuts are an under-recognized and under-consumed food in modern diets.”Nuts provide a variety of nutrients and can play an important role in the diet, especially for those who are eating a more plant-based diet.

Bruce, B., G.A. Spiller, L.M. Klevay, S.K. Gallagher, 2000 .A diet high in whole and unrefined foods favorably alters lipids, antioxidant defenses, and colon function. J Am Coll Nutr. 19(1):61-7.

This study involved 12 hyperlipidemic women in a crossover design that lasted for two 4-week periods.Subjects first consumed a refined-food diet and then switched to a phytochemical-rich diet primarily consisting of whole grains, legumes, fruits, vegetables, seeds and two tablespoons of almonds, hazelnuts or pecans per day.Compared to the refined-food diet, the phytochemical-rich diet lowered total cholesterol by 13% and LDL by 16% with no significant changes in HDL or triglycerides.

Bruce, B., G.A. Spiller, J.W. Farquhar, 1997 .Effects of a plant-based diet rich in whole grains, sun-dried raisins and nuts on serum lipoproteins. Veg Nutr. 1(2):58-63.

After four weeks of a diet rich in whole grains, sun-dried raisins and nuts, researchers saw an improvement in total and LDL cholesterol levels in 15 adults with elevated blood lipids.Both improved colon function and increased feelings of fullness were also seen with this plant-based diet containing unrefined, minimally processed foods.Further research is needed to identify additional positive effects of this diet on heart disease risk factors.

Colquhoun, D.M., 2000. Food for prevention of coronary heart disease: Beyond the low fat, low cholesterol diet. Asia Pacific J Clin Nutr. 9(suppl):S86-90.

Coronary heart disease (CHD) is now the single major cause of death worldwide.A low fat diet is almost universally recommended throughout the world.However, the most successful secondary prevention diet trials have used modification of fat, rather than just a decrease in total fat.For example, the Mediterranean-type diet, rich in antioxidants, fiber, nuts and wine, has been shown to help decrease LDL oxidation and improve endothelial function over the NCEP Step 2 diet.Therefore, until more research is done, the author recommends giving patients the choice of alternatives to a low fat diet, such as healthy cardioprotective cuisines from Greece, Spain, southern Italy, etc.

Cooke, J.P., P. Tsao, A. Singer, B.Y. Wang, J. Kosck, H. Drexler, 1993.Anti-atherogenic effect of nuts: is the answer NO? Arch Intern Med. 153:896, 899, 902.

In a commentary regarding the Seventh Day Adventist study, the authors highlight the fact that frequent nut consumption reduced the risk of experiencing fatal or nonfatal heart attacks by 50%.A possible explanation for the protective effect may be that nuts are high in arginine, a basic amino acid that is a precursor to nitric oxide (NO). The latter is known to inhibit plaque formation, or atherogenesis, which can lead to heart attacks. Studies have shown that people with hypercholesterolemia have reduced activity of NO.Adding arginine-rich nuts to the diet may help increase NO activity and thereby reduce the risk of heart attacks.

de Lorgeril et al, 1994. Mediterranean alpha-linolenic acid-rich diet in secondary prevention of heart disease. Lancet. 343(8911):1454-9

This study, also known as the Lyon Heart Study, is a prospective, randomized single-blinded secondary prevention trial with 605 subjects.The results showed essential fatty acids (EFAs) in the blood reduce clotting and inflammation, cutting risk for sudden heart attack and clogging of the arteries.Two grams of alpha-linolenic acid on a modified Crete Mediterranean diet reduced total death by 70%.

de Lorgeril, M., P. Salen, J-L. Martin, I. Monjaud, J. Delaye, N. Mamelle, 1999.Mediterranean diet, traditional risk factors, and the rate of cardiovascular complications after myocardial infarction. (Final report of the Lyon diet heart study.) Circulation. 99:779-85.

This study presents findings from an extensive follow-up to the Lyon Diet Heart Study, a randomized secondary prevention trial that looked at whether a Mediterranean type diet (which included nuts) could reduce the rate of recurrence after a first heart attack. An intermediate analysis showed a positive effect after 27 months of follow-up, this study looked at a mean of 46 months of follow-up per patient.The results showed a protective effect of the Mediterranean diet up to 4 years after the first heart attack. Major traditional risk factors, such as high blood pressure and high cholesterol, were shown to be independent and joint predictors of recurrence, indicating that the Mediterranean diet did not alter, qualitatively, the usual relationships between major risk factors and recurrence.The researchers concluded that a comprehensive strategy to decrease risk of cardiovascular morbidity and mortality should include a cardioprotective diet.This should be associated with other means (i.e., medications) aimed at reducing modifiable factors.

de Lorgeril, M., P. Salen, F. Laporte, F. Boucher, J. De Leiri, 2001.Potential use of nuts for the prevention and treatment of coronary heart disease: From natural to functional foods. Nutr Metab Cardiovasc Dis. 11:362-71.

This editorial discusses the research on nuts and coronary heart disease (CHD) and suggests that before using food technology to develop new and artificial foods to help patients follow what they think would be an “optimal diet,” scientists and physicians should first refer to the traditional diets of populations with low CHD rates.Studying the effect of natural or whole foods, such as nuts, should be a priority.According to the authors, natural foods are still the preferred functional foods because they may provide a better nutrient profile than any recomposed food, and the proportions of the various nutrients and non-nutrients are the result of a natural, and biologically compatible, evolution and not of an industrial process.

Dreher, M. L., Maher, C. V., Kearney, P.1996. The traditional and emerging role of nuts in healthful diets. Nutrition Reviews. 54:241.

This paper reviews the role of nuts throughout history and highlights the nutritional benefits of nuts, a well as the connection between frequent nut consumption and reduced incidence of coronary heart disease.

Durlach, J., Y. Rayssiquier, 1993. Fatty acid profile, fiber content and high magnesium density may protect against risk of coronary heart disease events. Magnes Res. 6:191-2.

Ellsworth, J.L., L.H. Kushi and A.R. Folsom, 2001 .Frequent nut intake and risk of death from coronary heart disease and all causes in postmenopausal women: The Iowa Women’s Health Study. Nutr Metab Cardiovasc Dis. 11:372-7.

This study looked at whether or not the risk of death due to coronary heart disease (CHD) and all causes is reduced in postmenopausal women who frequently consume nuts.In 1986, 34,111 postmenopausal women with no known cardiovascular disease reported the frequency of their consumption of nuts and other foods.After 12 years of follow-up, there was an inverse but not statistically significant association between frequent nut consumption (2 or more 1-ounce servings per week compared with less than one serving per month) and death from CHD.There was also a weak inverse association between frequent nut intake and all-cause mortality.In conclusion, frequent nut consumption may offer modest protection against the risk of death from all causes and CHD in postmenopausal women.

Estruch, R., M.A. Martínez-González, D. Corella, J. Salas-Salvadó, V. Ruiz-Gutiérrez, M.I. Covas, M. Fiol, E. Gómez-Gracia, M.C. López-Sabater, E. Vinyoles, F. Arós, M. Conde, C. Lahoz, J. Lapetra, G. Sáez, E. Ros, 2006. Effects of a Mediterranean-style diet on cardiovascular risk factors. Ann Intern Med. 145:1-11.

Researchers observed 772 asymptomatic individuals at high risk of CVD from the multicenter, randomized, primary prevention trial of cardiovascular disease (PREDIMED). Participants were assigned to a low-fat diet or to one of two Mediterranean diets. Those consuming the Mediterranean diets received either one liter of olive oil per week or 30 grams of nuts per day. After three months, compared to the low-fat diet, the two Mediterranean diets produced beneficial changes in most outcomes including blood glucose, systolic blood pressure and total cholesterol:HDL ratio. The researchers concluded that compared to the low-fat diet, the Mediterranean diets supplemented with olive oil or nuts had beneficial effects on cardiovascular disease.

Fraser, G.E., 1999.Nut consumption, lipids and risk of a coronary event. Clin Cardiol. 22(suppl. III):11-5.

The author gives an overview on the benefits of consuming nuts stating, “Four of the best and largest cohort studies in nutritional epidemiology have now reported that eating nuts frequently is associated with a decreased risk of coronary heart disease of the order of 30-50%.”He explains that possible mechanisms include the reduction of LDL cholesterol, the effects on the endothelium and platelet function of higher levels of nitric oxide, as well as the antioxidant properties of vitamin E.

Fraser, G.E., 1994.Diet and coronary heart disease: beyond dietary fats and low-density-lipoprotein cholesterol.Am J Clin Nutr. 59(suppl):1117S-23S.

For years researchers have been studying the effects of dietary fats and cholesterol on blood cholesterol levels, particularly LDL cholesterol levels.However, little attention has been given to the possible protective effect of specific foods. For example, nuts are high in unsaturated fats, which can lower total blood cholesterol and improve the lipoprotein profile; vitamin E in almonds and hazelnuts may prevent oxidation of LDL cholesterol (oxidized LDL can increase the risk of heart disease); fiber and plant sterols in nuts may lower LDL cholesterol; and magnesium and copper in nuts may also protect against heart disease.

Fraser, G.E., J. Sabaté, W.L. Beeson, T.M. Strahan, 1992.A possible protective effect of nut consumption on risk of coronary heart disease. Arch Intern Med. 152:1416-24.

This cohort investigation with 31,208 Seventh-day Adventists, which began in 1974, included detailed investigation of diet.Subjects who consumed nuts more than four times per week experienced substantially fewer definite fatal CHD events and definite nonfatal heart attacks than those who consumed nuts less than once per week. The results showed that nut consumption may reduce the risk of both fatal and nonfatal coronary heart disease.

Hu, F.B., 2003. Plant-based foods and prevention of cardiovascular disease: an overview. Am J Clin Nutr. 78:544S-51S.

This article highlights the benefits of plant foods, particularly nuts, in the prevention of heart disease.Nuts are high in unsaturated fats as well as important vitamins and minerals, which may provide the protective effects.

Hu, F.B., M.J. Stampfer, 1999.Nut consumption and risk of coronary heart disease: a review of epidemiologic evidence. Current Atherosclerosis Reports. (1):205-10.

This article proved an overview of the epidemiologic studies done on nuts and coronary heart disease.Given the strong evidence of the beneficial effects of nuts, the author recommends moving nuts to a “more prominent place” in the USDA Food Guide Pyramid.

Hu, F.B., M.J. Stampfer, J.E. Manson, E.B. Rimm, G.A. Colditz, B.A. Rosner, F.E. Speizer, C.H. Hennekens, W.C. Willett, 1998.Frequent nut consumption and risk of coronary heart disease in women: prospective cohort study. British Med J. 317:1341-5.

In this study, investigators analyzed links between diet and heart disease that showed up between 1980 and 1990, among 86,000 female nurses, ages 34-59.The researchers found that those who ate more than five ounces of nuts per week had one-third fewer heart attacks than those who rarely or never ate nuts.These data, and those from other epidemiological and clinical studies, support a role for nuts in reducing the risk of coronary hear disease.Preliminary results from the companion Physician’s Health Study suggest that frequent nut consumption may provide similar benefits to men.

Jenkins, D.J.A., D.G. Popovich, C.W.C. Kendall, E. Vidgen, N. Tariq, T.P.P. Ransom, T.M.S. Wolever, V. Vuksan, C.C. Mehling, D.L. Boctor, C. Bolognesi, J. Huang, R. Patten, 1997.Effect of a diet high in vegetables, fruit, and nuts on serum lipids. Metabolism. 46(5):530-7.

This study involved 10 adults in a randomized crossover design that lasted for two 2-week periods.The control diet was the subjects’ habitual diet.The study diet consisted of mainly vegetables, fruit, avocados and nuts (limited to 60-120g/day, average consumption was 100g/day).Compared to the control diet, total cholesterol was reduced by approximately 25%, LDL by 33% and triglycerides by 20%, with no significant change in HDL.

Key, T., G. Fraser, M.Thorogood, 1998. Mortality in vegetarians and non-vegetarians: a collaborative analysis of 8300 deaths among 76,000 men and women in five prospective studies. Pub Health Nutr. 1(1):33-41.

Klevay, L.M., 1993.Copper in nuts may lower heart disease risk. Arch Intern Med. 153: 401-2.

In this commentary on the Seventh-Day Adventist study, the author discuses the fact that nuts are relatively high in copper and that this may provide protection against a variety of disorders related to atherosclerosis.Copper deficiency is the only nutritional insult that has been shown to produce abnormal electrocardiograms, glucose intolerance, hypercholesterolemia, hypertension, hyperuricemia, injury by free radicals and thrombosis in animals.More than 31 men and women have responded to diets low in copper with potentially harmful changes in glucose tolerance, blood pressure, blood lipids and electrocardiograms.Copper in these daily diets ranged from 0.65 to 1.02 mg amounts.Eating an ounce of nuts can add approximately 0.37 mg of copper to daily intakes.

Krauss R.M., R.H. Eckel, B. Howard, L.J. Appel, S.R. Daniels, R.J. Deckelbaum, J.W. Erdman, Jr, P. Kris-Etherton, I.J. Goldberg, T.A. Kotchen, A.H. Lichtenstein, W.E. Mitch, R. Mullis, K. Robinson, J. Wylie-Rosett, S. St. Jeor, J. Suttie, D.L. Tribble, T.L. Bazzarre, 2001.Revision 2000: a statement for healthcare professionals from the Nutrition Committee of the American Heart Association. J Nutr. 131(1):132-46.

This scientific statement provides guidelines for reducing the risk of cardiovascular disease by dietary and other lifestyle practices. One of the guidelines for a desirable blood cholesterol and lipoprotein profile, suggests substituting grains and unsaturated fatty acids from vegetables, fish, nuts and legumes.

Kris-Etherton, P.M., S. Yu-Poth, J. Sabaté, H.E. Ratcliffe, G. Zhao, T.D. Etherton, 1999.Nuts and their bioactive constituents: effects on serum lipids and other factors that affect disease risk. Am J Clin Nutr. 70 (suppl.):504S-11S.

Researchers looked at the effects of nut-containing test diets on plasma lipids and lipoproteins, and compared the actual cholesterol response to the predicted response derived from the most current predictive equations for blood cholesterol.Results from the comparison showed that individuals who consumed test diets with nuts had a ~25% greater cholesterol-lowering response than predicted by the equations.The results suggest that there are non-fatty components in nuts that have cholesterol-lowering effects.

Kris-Etherton, P.M., G. Zhao, A.E. Binkoski, S.M. Coval, T.D. Etherton, 2001. The effects of nuts on coronary heart disease risk. Nutr Rev. 59:103.

Epidemiologic studies have shown again and again the beneficial effects of nut consumption on coronary heart disease morbidity and mortality in various population groups.Clinical studies have shown total and low-density lipoprotein cholesterol-lowering effects of nut-containing heart-healthy diets.The beneficial effects of nuts include their fatty acid profile, dietary fiber and other bioactive components that may offer additional cardioprotective effects.

Kushi, L.H., A.R. Folsom, R.J. Prineas, P.J. Mink, Y. Wu, R.M. Bostick, 1996.Dietary antioxidant vitamins and death from coronary heart disease in postmenopausal women. NEJM. 334:1156-62.

The “Iowa Women’s Health Study” looked at 35,000 postmenopausal women with no cardiovascular disease, over a seven-year period (1986-1992).The researchers observed that women who ate nuts and seeds more than four times a month had a 40% reduction in risk of coronary heart disease compared to those who never ate nuts or seeds.

Lairon, D., N. Arnault, S. Bertrais, R. Planells, E. Clero, S. Hercberg, M.-C. Boutron-Ruault. Dietary fiber intake and risk factors for cardiovascular disease in French adults. Am J Clin Nutr. 82:1185-94.

This cross-sectional study looked at the relation between the source or type of dietary fiber intake and cardiovascular disease risk factors in a cohort of 2532 adult men and 3429 adult women. The highest total dietary fiber and nonsoluble dietary fiber intakes were associated with a significantly (P_0.05) lower risk of overweight and elevated waist-to-hip ratio, blood pressure, plasma apolipoprotein (apo) B, apo B:apo A-I, cholesterol, triacylglycerols, and homocysteine. Soluble dietary fiber was less effective. Fiber from dried fruit or nuts and seeds was associated with a lower body mass index, waist-to-hip ratio, and fasting apo B and glucose concentrations. The researchers concluded that dietary fiber intake is inversely correlated with several cardiovascular disease risk factors in both sexes, which supports its protective role against cardiovascular disease and recommendations for its increased consumption.

Lapointe, A., J. Goulet, C. Couillard, B. Lamarche, S. Lemieux, 2005. A nutritional intervention promoting the Mediterranean food pattern is associated with a decrease in circulating oxidized LDL particles in healthy women from the Québec City metropolitan area. J. Nutr. 135:410-15.

This study evaluated the effect of a Mediterranean diet that included nuts, under free living conditions, on circulating oxidized LDL (ox-LDL) in a group of 71 healthy women. The 12-week intervention included 2 courses on nutrition and 7 individual sessions with a dietitian. Among all women, plasma ox-LDL decreased by 11.3% after 12 weeks of nutritional intervention despite a lack of change in plasma LDL cholesterol. The authors concluded that changes in the food pattern in response to a nutritional intervention promoting the Mediterranean diet were accompanied by beneficial effects in circulating ox-LDL concentrations in healthy women.

Mantzoros, C.S., C.J. Williams, J.E. Manson, J.B. Meigs, F.B. Hu, 2006. Adherence to the Mediterranean dietary pattern is positively associated with plasma adiponectin concentrations in diabetic women. Am J Clin Nutr. 84:328-35.

In this study, researchers examined the effect of the Mediterranean diet on adiponectin concentrations. Adiponectin is an adipose tissue-secreted cytokine that has been shown to regulate glucose and lipid metabolism, improve insulin sensitivity and have pronounced antiatherosclerotic effects. Researchers evaluated dietary data and plasma adiponectin in 987 diabetic women, with no history of cardiovascular disease, from the Nurses’ Health Study. Women with the greatest adherence to a Mediterranean-type diet had higher plasma adiponectin concentrations than women with the lowest adherence. The data suggested that several components of the Mediterranean diet (alcohol, nuts and whole grains) showed the strongest association with higher concentrations of adiponectin.

Mukuddem-Petersen, J., W. Oosthuizen, J. C. Jerling. 2005. A systematic review of the effects of nuts on blood lipid profiles in humans. Nutrition 135; 2082-2089.

Medline and Web of Science databases were searched from the start of the database to August 2004 and supplemented by cross-checking reference lists of relevant publications. Human intervention trials with the objective of investigating independent effects of nuts on lipid concentrations were included. From the literature search, 415 publications were screened and 23 studies were included. These papers received a rating based upon the methodology as it appeared in the publication. No formal statistical analysis was performed due to the large differences in study designs of the dietary intervention trials. The results of 3 - 14 - August 2006 almond (50-100 g/d), 2 peanut (35-68 g/d), 1 pecan nut 72 g/d), and 4 walnut (40-84 g/d) studies showed decreases in total cholesterol between 2 and 16% and LDL cholesterol between 2 and 19% compared with subjects consuming control diets. Consumption of macadamia nuts (50-100 g/d) produced less convincing results. In conclusion, consumption of ~50-100 g(~1.5-3.5 servings) of nuts ≥5 times/wk as part of a heart-healthy diet with total fat content (high in mono- and/or polyunsaturated fatty acids) of ~35% of energy may significantly decrease total cholesterol and LDL cholesterol in normo- and hyperlipidemic individuals.

Nash, S.D., M. Westpfal, 2005. Cardiovascular benefits of nuts. American Journal of Cardiology. 963-65.

This review article highlights some of the cardiovascular benefits of nuts. The authors conclude by writing, “Simply stated, at a time of spiraling costs for medical care, public and professional concerns about drug safety, and in an age of fad diets, it is reassuring to have a “nutty alternative.”

Sabaté, J., 1993. Does nut consumption protect against ischaemic heart disease? Eur J of Clin Nutr. 47(suppl.1):S71-5.

Results of an epidemiological study conducted among California Adventists provides strong evidence that frequent nut consumption has a protective effect on both fatal and non-fatal ischaemic heart disease.It’s plausible, due to the unique composition of nuts, that nuts favorably affect heart disease risk factors and interfere with the process of atherogenesis.Results of human nutritional studies, with varying degrees of methodological rigor all seem to indicate that eating nuts lowers serum cholesterol and favorably modifies the lipoprotein profile.

Sabaté, J., 1999. Nut consumption, vegetarian diets, ischemic heart disease risk, and all-cause mortality: evidence from epidemiologic studies. Am J Clin Nutr. 70(suppl):500S.

A number of large epidemiologic studies have shown that frequency of nut consumption has a substantial and significant inverse association with risk of myocardial infarction and death from ischemic heart disease (IHD). In addition, frequency of nut consumption has been found to be inversely related to all-cause mortality in several population groups including the elderly, blacks and whites.The author concludes that nut consumption may not only offer protection against IHD, but also increase longevity.

Sabaté J., G.E. Fraser, 1994. Nuts: a new protective food against coronary heart disease. Current Opinion in Lipidology. 5:11-16.

Epidemiological findings indicate that eating nuts frequently may help protect against fatal and non-fatal heart disease, including heart attacks.Although preliminary studies indicate that nut consumption lowers total and LDL cholesterol levels, the unique nutrient composition of nuts may decrease risk of heart disease in other ways too.This article provides a review of the epidemiological evidence linking nut consumption with coronary heart disease, and addresses some of the biological mechanisms by which nut consumption may reduce coronary risk.

Sabaté J., D.G. Hook. Almonds, walnuts, and serum lipids.In: Spiller, G.A. Handbook of Lipids in Human Nutrition .New York, NY: CRC Press, Inc.; 1996.

This chapter reviews human studies that look at the effects of whole almonds and walnuts on blood lipid levels. Although each of the studies differ in methodology, the overriding consensus is that almonds, walnuts, and possibly other nuts with a similar nutrient composition, have a cholesterol lowering effect.The protective effect of nuts on coronary heart disease may be due to their fatty acid composition (mostly unsaturated fats) and other components in nuts.

Sacks, F.M., L.P. Svetkey, W.M. Vollmer, L.J. Appel, B.A. Bray, D. Harsha, E. Obarzanek, P.R. Conlin, E.R. Miller, D.G. Simons-Morton, N. Karanja, P. Lin,2001. Effects on blood pressure of reduced dietary sodium and the dietary approaches to stop hypertension (DASH) diet. NEJM. 344:3.

Singh, R.B., G. Dubnov, M.A. Niaz, S. Ghosh, R. Singh, S.S. Rastogi, O. Manor, D. Pella, E.M. Berry, 2002. Effect of an Indo-Mediterranean diet on progression of coronary artery disease in high-risk patients (Indo-Mediterranean Diet Heart Study): a randomized single-blind trial. Lancet . 360:1455-61.

This randomized, single-blind trial in 1000 patients with angina pectoris, heat attack, or surrogate factors for coronary artery disease (CAD), compared an Indo-Mediterranean (IM) diet to the NCEP Step 1 diet. 499 patients were allocated the IM, or intervention diet, which included whole grains, fruits vegetables, walnuts and almonds. 501 controls consumed a local diet similar to the Step 1 diet.Total cardiac endpoints were significantly fewer in the intervention group than in the control group; sudden cardiac deaths were also reduced as were non-fatal heart attacks.There was also a significant reduction in serum cholesterol and other risk factors in both groups, but more so in the intervention group.The results indicate that an Indo-Mediterranean diet may be more effective in primary and secondary prevention of CAD than the conventional Step 1 NCEP diet.

Singh, R.B., S.S. Rastogi, R.Verma, L. Bolaki, R. Singh, 1992. An Indian experiment with nutritional modulation in acute myocardial infarction. Am J Cardiol. 69:879-85.

This study involved 406 patients who were recruited 24 to 48 hours after having an acute myocardial infarction (MI).The randomized, single-blind intervention study lasted 6 weeks.Subjects were divided into two groups.One group consumed Diet A in which meat and eggs were replaced by fish, vegetarian meat substitutes and nuts (almonds and walnuts).Those following Diet B ate a low-calorie, typical hospital diet, followed by a diet prescribed by their doctors.Those consuming Diet A had a 9% decrease in total cholesterol, 10% decrease in LDL and 9% decrease in triglycerides.Those following Diet A also had a 36% decrease in cardiovascular events compared to those consuming Diet B.

Svetkey L.P., F.M. Sacks, E. Obarzanek, W.M. Vollmer, L.J. Appel, P.H. Lin, N.M. Karanja, D.W. Harsha, G.A. Bray, M. Aickin, M.A. Proschan, M.M. Windhauser, J.F. Swain, P.B. McCarron, D.G. Rhodes, R.L. Laws, 1999. The DASH diet, sodium intake and blood pressure trial (DASH-sodium): rationale and design. DASH-sodium collaborative research group. J Am Diet Assoc (8 suppl):S96-104.

Verschuren, W.M.M., E.M. van Leer, A. Blockstra, J.C. Seidell, H.A. Smit, H.B. Bueno de Mesquita, G.L. Oberman-de Boer, D. Kromhout, 1993. Cardiovascular disease risk factors in the Netherlands. Neth J Cardiol. 4:205-10.

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DIABETES

American Diabetes Association (ADA).2003.Evidence-based nutrition principles and recommendations for the treatment and prevention of diabetes and related complications (Position Statement). Diabetes Care. 26(suppl.1): S51–61.

This position statement promotes the use of individualized medical nutrition therapy for people with diabetes, with consideration given to each individual’s usual food and eating habits, treatment goals, metabolic profile and desired outcomes.

Brand-Miller, J, S. Hayne, P. Petocz, S. Colagiuri, 2003. Low-glycemic index diets in the management of diabetes. Diabetes Care. 26(8):2261-66.

This meta-analysis of randomized controlled trials, including 14 studies and 356 subjects, compared the use of diets with low glycemic index (GI) to conventional or high-GI diets on overall glycemic control in individuals with diabetes, as assessed by reduced HbA_1c or fructosamine levels. The results showed that low GI diets reduced HbA_1c by 0.43% points more than the high-GI diets. Looking at HbA_1c and fructosamine together, glycated proteins were reduced 7.4% more on the low-GI diet than on the high-GI diet. The researchers concluded that choosing low-GI foods in place of conventional or high-GI foods has a small but useful effect on medium-term glycemic control in diabetics. The incremental benefit is similar to that seen with drugs that also target postprandial hyperglycemia. [While this study does not mention nuts specifically, they are a very low-GI food.]

Garg A., 1998. High monounsaturated fat diets for patients with diabetes mellitus: a meta-analysis. Am J Clin Nutr. 67(suppl):577s-82s.

A meta-analysis of various studies was conducted to compare either low-saturated fat, high-carbohydrate diets or high-monounsaturated fat diets in patients with Type II diabetes.The results show that the high-monounsaturated fat diets improve lipoprotein profiles as well as the glycemic profile, compared to the low-saturated fat, high-carbohydrate diets.The high-monounsaturated fat diets reduced fasting plasma triacylglycerol and VLDL-cholesterol levels by 19% and 22% respectively, and caused modest increases in HDL-cholesterol without negatively impacting LDL-cholesterol. The high-monounsaturated fat diets may also reduce the susceptibility of LDL particles to oxidation and thereby reduce their atherogenic potential.Moreover, there is no evidence that high-monounsaturated fat diets cause weight gain in patients with diabetes, provided that caloric intake is controlled. The researcher concluded that diets rich in monounsaturated fat can be useful and advantageous for both patients with Type I or Type II diabetes who are trying to lose or maintain weight. [Most nuts are rich in monounsaturated fats.]

García-Lorda, P. I. M. Rangil, J. Salas-Salvadó, 2003. Nut consumption, body weight and insulin resistance. Eur J Clin Nutr. 57(suppl 1):S8-S11.

Since nuts provide a high amount of fat and calories, there has been some concern that they may have a detrimental effect on body weight and insulin resistance.However, according to the authors, the current data available does not support such a negative effect of nut consumption on the short term or when nuts are included on diets that meet energy needs.There is some evidence that nuts may actually help regulate body weight and protect against Type II diabetes, but more research is needed.

Jenkins, D.J., T.M. Wolever, B. Buckley, et al., 1988. Low-glycemic-index starchy foods in the diabetic diet. Am J Clin Nutr. 48:248-54.

Eight patients with noninsulin-dependent diabetes were provided, in random order, with carbohydrate foods with either low or high glycemic index (GI) during two, 2-week study periods. While weight loss occurred in both the low- and high-GI periods, only during the low-GI period were significant reductions seen in fasting blood glucose, HbA_1c, and urinary c-peptide-to-creatinine ratio. The researchers concluded that inclusion of low-GI foods into diets of patients with diabetes may be an additional measure that favorably influences carbohydrate metabolism without increasing insulin demand. [While this study does not mention nuts specifically, they are a very low-GI food.]

Jenkins, D.J.A., T.M.S. Wolever, R.H. Taylor, et al., 1981. Glycemic index of foods: a physiological basis for carbohydrate exchange. Am J Clin Nutr. 34:362-6.

In order to determine the effect of different foods on blood glucose levels, groups of 5-10 healthy, fasting volunteers were fed 62 commonly eaten foods, individually. Blood glucose levels were measured over two hours.The largest rises were seen with vegetables, breakfast cereals, cereals and biscuits, followed by fruit, dairy products and dried legumes (including peanuts).There was a significant negative relationship between protein and fat and postprandial glucose rise, but not with fiber or sugar content.

Jiang, R., J.E. Manson, M.J. Stampfer, S. Liu, W.C. Willett, F.B. Hu, 2002. Nut and peanut butter consumption and risk of type 2 diabetes in women. JAMA. 288:2554-60.

This prospective cohort study looked at 83,818 women from 11 states in the Nurses’ Health Study, aged 34-59, with no history of diabetes, cardiovascular disease or cancer.The subjects completed a validated dietary questionnaire at baseline in 1980 and were followed up for 16 years.According to the researchers, the findings suggest potential benefits of higher nut and peanut butter consumption in lowering risk of type 2 diabetes in women. To avoid increasing caloric intake, regular nut consumption can be recommended as a replacement for consumption of refined grain products or red or processed meats.

Lopez-Ridaura, R., W.C. Willett, E.B. Rimm, S. Liu, M.J. Stampfer, J.E. Manson, F.B. Hu, 2004.Magnesium intake and risk of type 2 diabetes in men and women. Diabetes Care. 27(1): 134-40.

Researchers followed 85,060 women and 42,872 men in the Nurses’ Health Study and Health Professionals’ Follow-up Study, respectively, with no history of diabetes, cardiovascular disease or cancer at baseline. Magnesium intake was monitored every 2-4 years via a food frequency questionnaire.After 18 years of follow-up in women and 12 years in men, there were 4,085 and 1,333 incident cases of type 2 diabetes, respectively.The results showed a significant inverse association between magnesium intake and diabetes risk.This study supports the recommendation to increase consumption of magnesium-rich foods such as nuts, whole grains and green leafy vegetables.

Luscombe, N., M. Noakes, P. Clifton, 1999. Diets high and low in glycemic index versus high monounsaturated fat diets: effects on glucose and lipid metabolism in NIDDM. Eur J Clin Nutr. 53:473-8.

This study compared high and low glycemic index (GI) carbohydrates (CHO) and monounsaturated fats (mono) on blood glucose and lipid metabolism in free-living outpatients with non-insulin dependent diabetes mellitus (NIDDM).Each subject consumed three diets: a high-GI diet (53% CHO, 21% fat, 63 GI units); a low-GI diet (51% CHO, 23% fat, 43 GI units); and a high-mono, high-GI diet (42% CHO, 35% fat, 59 GI units) in random order and cross-over fashion for four weeks. Each of the diets contained more than 30 grams of dietary fiber and the high-mono, high-GI diet included almonds. At the end of the study, HDL-cholesterol was higher on the low-GI and high-mono, high-GI diets, compared to the high-GI diet. Saturated fat intake and body weight remained stable between the dietary interventions.The researchers concluded that the high-mono, high-GI and high-CHO, low-GI diets are superior to high-CHO, high-GI diets with respect to HDL metabolism, but there was no effect noted on glucose metabolism in variably controlled NIDDM patients.

Miller, J.C., 1994.Importance of glycemic index in diabetes. Am J Clin Nutr. 59:747S-52S.

This article reviewed 11 medium to long-term studies that have specifically used the glycemic index (GI) to assess the clinical benefits in diabetes or lipid management.All but one study showed positive results.Overall, low-GI diets lowered glucose, cholesterol and triglycerides in modest amounts.And, unlike high-fiber diets, low-GI diets are “use friendly.” According to the author, the time has come to reassess the value of GI in planning meals for diabetics. [While this study does not mention nuts specifically, they are a very low-GI food.]

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GALLSTONES

Tsai, C-J., M.F. Leitzmann, F.B. Hu, W.C. Willett, E.L. Giovannucci, 2004. Frequent nut consumption and decreased risk of cholecystectomy in women. Am J Clin Nutr. 80:76-81.

Researchers analyzed the potential link between nuts and cholecystectomy, or gallstones, between 1980 and 2000, among 80,718 women from the Nurses’ Health Study who were 30-55 years old in 1980 and had no history of gallstone disease.After adjusting for age and other known suspected risk factors, researchers found that women who consumed 5 or more ounces of nuts per week had a significantly lower risk of gallstones than women who rarely or never ate nuts.The authors of the study concluded that frequent nut consumption in women is associated with a reduced risk of cholecystectomy.

Tsai, C-J., M.F. Leitzmann, F.B. Hu, W.C. Willett, E.L. Giovannucci, 2004. The effect of long-term intake of cis unsaturated fats on the risk of gallstone disease in men. Ann Intern Med. 141:514-22.

This prospective, population-based study involved 45,756 men from the Health Professional’s Follow-up Study, who were 40-75 years old in 1986 and had no history of gallstone disease.After 14 years of follow-up those with high intakes of both monounsaturated and polyunsaturated fatty acids had fewer self-reported cases of symptomatic gallstone disease than those with low intakes.The authors concluded that long-term intake of high amounts of cis unsaturated fat seems to be associated with a decreased risk of gallstone disease in men.[While nuts were not mentioned specifically in this study, they are very high in mono- and polyunsaturated fats.]

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GENERAL

Knoops, K.T.B., L.C.P.G.M. de Groot, D. Kromhout, A-E. Perrin, O. Moreiras-Varela, A. Menotti, W.A. van Staveren, 2004.Mediterranean diet, lifestyle factors, and 10-year mortality in elderly men and women. JAMA. 292:1433-39.

In this study of Europeans, aged 70-90 years, adherence to a Mediterranean diet (that included nuts) and healthful lifestyle (moderate alcohol, physical activity and no smoking) was associated with more than a 50% lower rate of all-causes and cause-specific mortality.

Lin, B.H., E. Frazao, J. Allhouse, 2001. U.S. consumption patterns of tree nuts. Food Review. 24(2):54-8.

Lino, M., K. Marcoe, J.M. Dinkins, H. Hiza, R. Anand, 2000. USDA Center for Nutrition Policy and Promotion. The role of nuts in a healthy diet. Insight 23, December.

Mann, J.I., 2000.Optimizing the plant-based diet. Asia Pacific J Clin Nutr. 9(suppl):S60-4.

This review looks at the major health benefits of plant-based diets, the specific foods which provide the potential benefits and potential nutrient deficiencies.According to the author, of all the individual potential protective foods from studies to date, consumption of nuts is of particular interest.Nuts appear to provide identical protective effects to both vegetarians and non-vegetarians and seem to be inversely related to all-cause mortality, thus possibly promoting longevity as well as reducing cardiovascular risk. The possible mechanisms by which nuts may protect against heart disease include a favorable fatty acid profile, their cholesterol lowering potential and the presence of a wide range of bioactive compounds.

Noah, A., A.S. Truswell, 2001.There are many Mediterranean diets. Asia Pacific J Clin Nutr. 10(1):2-9.

This paper provides an overview of the various Mediterranean diets from 20 to 30 years ago.Interestingly, not all Mediterranean countries consume the same foods or the same amounts of foods.In the case of nuts, almonds were consumed 3-5 times per week in Italy and Morocco, but 6-7 times per week in Lebanon and Turkey.Pistachios were consumed rarely in Italy, but 3-5 times per week in Lebanon and 6-7 times per week in Turkey.The authors conclude that there is no single Mediterranean diet and nutritionists who use the concept should qualify the individual country and the time in history of their “model” Mediterranean diet.

Oldways, 1995.Tree nuts, health and the Mediterranean diet. A summary report. Boston, USA. 51 pages.

Rainey, C., L. Nyquist, 1997. Nuts – nutrition and health benefits of daily use. Nutrition Today. 32(4):157-63.

This article dispels many of the myths about the role of nuts in the diet and provides a nice overview on the nutritional benefits and uses of nuts.

Spiller, G.A., B. Bruce, 1997.Nuts and healthy diets. Vegetarian Nutrition: An International Journal. 1(1):12-16.

This paper examines the history and composition of a variety of nuts from around the world and concludes that nuts are under-consumed in modern diets.Nuts provide an abundance of nutritional value and can play an important role as individuals move from animal-based diets to plant-based diets.

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MENARCHE

F.J. Soriguer, S. Gonzalez-Romero, I. Esteva, J.A. Garcia-Arnes, F. Tinahones, M.S. Ruiz De Adana, G. Olveira, I. Mancha, F. Vazques, 1995. Does the intake of nuts and seeds alter the appearance of menarche? Acta Obstet Gynecol Scand. 74:455-61.

A cross-sectional study of 777 schoolgirls in Spain, ages 8-16 years, found that in girls 12-years or older, the age of menarche was essentially related to the intake of nuts and seeds.The study concluded that girls who eat larger amounts of nuts and seeds tend to have their menarche delayed.

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WEIGHT CONTROL

Kirkmeyer, S.V, R.D. Mattes, 2000. Effects of food attributes on hunger and food intake. Int J Obesity. 24:1167-75.

Preloads of almonds, peanuts, peanut butter, chestnuts, chocolate, rice cakes and pickles were consumed in random order at weekly intervals by 12 male and 12 female healthy, normal weight adults. Hunger was assessed after consumption of 500 calories of a particular preload over the subsequent three hours. The researchers concluded that energy content of a preload may exert a stronger influence on hunger, in the subsequent 180 minutes, than the food’s energy density, macronutrient profile, fiber content, weight, volume, rheology or sensory properties.

McManus, K., L. Antinoro, F. Sacks, 2001.A randomized controlled trial of a moderate fat, low energy diet compared with a low fat, low energy diet for weight loss in overweight adults. Int J Obesity. 25:1503-11.

In this randomized, parallel study, 101 overweight adults were followed for 18 months.Subjects were divided into two groups and consumed one of two study diets, both of which were calorie controlled (1200 kcal/day for women; 1500 kcal/day for men).The low-fat diet (LF) had a total of 20% calories from fat, while the high-unsaturated fat diet (UNSAT) consisted of 35% total fat and included tree nuts, peanuts, canola and olive oils.

After six months the average weight loss was comparable in both groups. However, there was a significant difference at the end of the 18 months in participation rates. In the LF group, only 20% were still actively participating in the study compared to 54% of the UNSAT group. One factor which may contribute to the greater participation rate, is that a moderate fat diet may induce the feelings of satiety after a snack or meal. In addition, the participants in the UNSAT group reported that they did not feel like they were “dieting” and therefore, did not feel deprived.

Piers, L.S., K.Z. Walker, R.M. Stoney, M.J. Soares, K. O’Dea, 2003. Substitution of saturated with monounsaturated fat in a 4-week diet affects body weight and composition of overweight and obese men. British Journal of Obesity. 90:717-27.

This randomized crossover study tried to determine whether or not substituting saturated fat (SF) with monounsaturated fat (MUFA) effects body weight and composition.Eight overweight or obese men followed two diets for four weeks each.The MUFA diet included nuts, olive oil and avocado, while the SFA diet was rich in milk, butter, cream, cheese and fatty meat.At the end of the study the men had lost more weight and fat mass on the MUFA diet than on the SFA diet.The researchers concluded that substituting SFA with unsaturated fats, particularly MUFA, can result in a small but significant loss of body weight and fat mass without a significant change in fat intake or total calories.

Sabaté, J., 2003.Nut consumption and body weight. Am J Clin Nutr. 78(suppl):647S-50S.

According to the author, the available data demonstrate that nut consumption among free-living individuals is not associated with higher BMI compared with non-nut consumers despite the fact that nuts are fat- and energy-dense foods. Isocaloric replacement of nuts for other food in the diet does not increase weight. While more research is needed in this area, the current data do not indicate that free-living people on self-selected diets including nuts frequently have a higher BMI or increased body weight.

Sabaté, J., G. Blix, 2001.Vegetarian diets and obesity prevention. In: Sabaté, J., (ed.), Vegetarian Nutrition. CRC Press, Boca Raton, 91-107.

St-Onge, M.P., 2005. Dietary fats, teas, dairy, and nuts: potential functional foods for weight control? Am J Clin Nutr. 81:7-15.

Nuts are one of the foods highlighted in this review paper on functional foods and weight control. While few studies have been conducted specifically on nuts and weight control, a number of supplementation studies looking at nuts and lipid profiles have not found negative effects on body weight. In fact, a majority of the papers reviewed here show no weight gain despite the additional calories from nuts. The author concludes that although more research is needed, nuts may play a role in weight maintenance via increased satiety levels, increased resting energy expenditure or energy malabsorption.

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NUTRIENT COMPOSITION

Borchers, A., 2001. Review of the Scientific Literature on Phenolic Compounds and Phytosterols in Tree Nuts. (Unpublished 28-page report for INC with 279 references.)

Numerous epidemiological studies suggest that higher consumption of plant products (fruits, vegetables, nuts and grains) is associated with a decreased risk of heart disease, cancer, and possibly other chronic diseases.There are many indications that, in addition to antioxidant vitamins, a variety of phytochemicals may contribute to these health benefits of plant-derived foods.There are a variety of candidates – including fiber, arginine, the lysine:arginine ratio, copper, magnesium, phenolic compounds, and phytosterols.Similarly, phenolic compounds as well as phytosterols are thought to be among the plant constituents that play a role in lowering the risk of various cancers.

This report consists of two major sections, I) phenolic compounds in tree nuts and II) phytosterols in tree nuts, followed by several appendices summarizing information on dietary sources and intake of phenolic compounds, their bioavailability and their metabolism.

Chai, W., M. Liebman, 2005. Oxalate content of legumes, nuts and grain-based flours. Journal of Food Composition and Analysis. 18:723-29.

This study looked at the oxalate content of legumes, nuts and grain-based flours since dietary oxalate can make a significant contribution to urinary oxalate levels, which can lead to kidney stones. The range of total oxalate of the nuts tested was 42-469 milligrams per 100 grams of nuts—making nuts a rich source of oxalate.

Hopper, K., B. Lampi, E. O’Grady, 1994.Biotin content in vegetables and nuts available on the Canadian market. Food Research International. 27:495-7.

The mean total biotin levels for nuts and seeds varied from 0.7 to 91.1 micrograms/100 grams.

Gu, L., M.A. Kelm, J.F. Hammerstone, G. Beecher, J. Holden, D. Haytowitz, S. Gebhardt, R.L. Prior, 2004.Concentrations of proanthocyanidins in common foods and estimations of normal consumption. J Nutr. 134:613-17.

Proanthocyanidins (PAs) have been shown to have potential health benefits, however, until now no data existed concerning their dietary intake.This study analyzed the PAs in common and infant foods in the U.S. Tree nuts were found to contain a substantial amount of PAs.The results showed that PAs account for a major fraction of the total flavonoids ingested in Western diets.More research is needed to study the association between varying amounts of Pas and their effects on different diseases.

Kornsteiner, M., K.H. Wagner, I. Elmadfa, 2005. Tocopherols and total phenolics in 10 different nut types. Food Chemistry. 98:381-87.

Kornsteiner et al. (2005) looked at tocopherols and total phenolics in 10 different types of nuts. Almonds and hazelnuts had the highest concentrations of a-tocopherol and pistachios had the only detectable levels of carotenoids. The mean content of total phenolics ranged from 32 milligrams of gallic acid equivalents/100 grams of pine nuts, to1,625 milligrams in walnuts. The researchers concluded that due to the heterogenic amounts of antioxidants in nuts, it’s best to consume a variety of mixed nuts.

Venkatachalam, M., S.K. Sathe. 2006. Chemical Composition of Selected Edible Nut Seeds. J Agric Food Chem. 54, 4705-4714.

Commercially important edible nut seeds were analyzed for chemical composition and moisture sorption. Moisture (1.47-9.51%), protein (7.50-21.56%), lipids (42.88-66.71%), ash (1.16-3.28%) total soluble sugars 0.55-3.96%), tannins (0.01-0.88%) and phytate (0.15-0.35%) contents varied considerably. Regardless of the seed type, lipids were mainly composed of mono- and polyunsaturated fatty acids (>75% of the total lipids). Fatty acid composition analysis indicated that oleic acid was the main constituent of monounsaturated lipids in all seed samples. With the exception of macadamia, linoleic acid (C18:2) was the major polyunsaturated fatty acid. In the case of walnuts, in addition to linoleic acid (58.79%) linolenic acid also significantly contributed toward the total polyunsaturated lipids.

Wu, X., Beecher, G.R., Holden, J.M., Haytowitz, D.B., Gebhardt, S.E., R.L. Prior, 2004.Lipophilic and hydrophilic antioxidant capacities of common foods in the United States. J Agric Food Chem. 52:4026-37.

This paper looks at the lipophilic and hydrophilic ORACFL values for over 100 common foods in the U.S., including nuts. Total phenolic concentrations were also measured. The authors note that nuts are an important source of dietary lipids and have been suggested as a potential source of dietary antioxidants on the basis of recent epidemiological and cohort studies. While more research is needed, this paper gives a nice overview of both the antioxidant capacity and phenolic content of nuts.

Wu, X., R.L. Prior, 2005. Identification and characterization of anthocyanins by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry in common foods in the United States: vegetables, nuts, and grains. J Agric Food Chem. 53:3101-13.

Anthocyanins in common foods in the United States, other than fruits and berries, were identified and characterized by high-performance liquid chromatography (HPLC)-electrospray ionizationtandem mass spectrometry coupled with diode array detection. Of all of the 40+ vegetables, nuts, and grains screened, seven vegetables, one nut, and one grain were found to contain anthocyanins; the number of anthocyanins detected varied from two in pistachio nuts (cyanidin 3-galactoside and cyanidin 3-glucoside) to 34 in red radishes.

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ALMOND REFERENCES

Acosta, M.R., K.H. Roux, S.S. Teuber, S.K. Sathe, 1999. Production and characterization of rabbit polyclonal antibodies to almond (Prunus amygdalus L) major storage protein. J Agric Food Chem. 47: 4053-9.

The results of this study demonstrate the feasibility of developing an immunobased assay to detect the presence of small amounts of almonds in food products. The researchers believe that when further developed, this assay will be of value to the food industry and allergic individuals for the detection of almond contamination in foods.

Burton-Freeman, B., P.A. Davis, B.O. Schneeman, 2004. Interaction of fat availability and sex on postprandial satiety and cholecystokinin after mixed-food meals. Am. J. Clin. Nutr. 80:1207-14.

The satiety response to a dietary fat provided as almond oil or whole almonds was influenced by sex and appeared to be dependant on the availability of the fat to stimulate CCK release in women but not in men. The effect of fat availability appears to be less important to satiety –related processes in men. These data support the need for continued research in this area to better understand sex-specific differences mechanistically and outcomes behaviorally in order to design diets that provide optimal food intake control and satiety.

Davis, P.A., and C.K. Iwahashi, 2001. Whole almonds and almond fractions reduce aberrant crypt foci in a rat model of colon carcinogenesis. Cancer Letters. 165:27-33.

A research study in rats showed that almond consumption may provide a measure of protection from the risk of developing colon cancer.The findings that almonds might provide a measure of protection from the risk of chronic diseases suggests a need to reassess the current view that intake of high fat foods invariably has deleterious health effects.This suggests that almonds might have chemopreventive agents against colon carcinogenesis.

Davis, P., C.K. Iwahashi, W. Yokoyama, 2003. Whole almonds activate gastrointestinal (GI) tract anti-proliferative signaling in APCmin (multiple intestinal neoplasia) mice. FASEB Journal. 17(5):A1153.

Most recently, researchers used a genetic mouse model and examined the effects of whole almonds versus almond-component-containing diets on the APC min mouse.Whole almonds activated GI tract anti-proliferative signaling, which might give a mechanistic explanation of almonds’ chemo-protective effect.

Dourado, F., A. Barros, M. Mota, M.A. Coimbra, F.M. Gama, 2004. Anatomy and cell wall poly-saccharides of almond (Prunus dulcis D.A. Webb) seeds. J Agric Food Chem. 52:1364-1370.

Portuguese almond seed anatomy was analyzed by various staining techniques and light microscopy. The almonds seed coat is thin and structurally complex, with lignified celluosic tissue. The almond kernel cell walls are rich in arabinose (45%) glucose (23%) uronic acids (12%) and xylose (12%).

Ellis, P.R., Kendall, C.W.C., Ren, Y., Parker, C., Pacy, J.P., Waldron, K.W., D.J.Q. Jenkins, 2004. Role of cell walls in the bioaccessibility of lipids in almond seeds. Am J Clin Nutr. 80:604-13.

In a series of experiments, researchers evaluated the effects of mechanical disruption, chewing and digestion on almond seed microstructure and intracellular lipid release.In the digestibility study, fecal samples were collected from healthy subjects who had consumed diets with or without almonds.The samples and almond seeds were examined by microscopy to identify cell walls and intracellular lipid.During mechanical methods or chewing, only the first layer of cells at the fractured surface was ruptured and able to release lipid.In the fecal samples of subjects who consumed almonds, intact cells containing intracellular lipid were found.In conclusion, the cell walls of almond seeds reduce lipid absorption in the intestine by hindering the release of lipid available for digestion.

Fraser, G.E., H.W. Bennett, K.B. Jaceldo, J. Sabaté, 2002. Effect on body weight of a free 76 kilojoules (320 calorie) daily supplement of almonds for 6 months.J Am Coll Nutr. 21(3): 275-83.

A one-year clinical study evaluating the long-term effect of eating almonds daily on dietary patterns, displacement of foods and selected nutrients and satiety, concluded that adding a modest quantity of almonds (approximately 2 ounces) to the diet regularly resulted in increased unsaturated fat intake with no significant changes in body weight.Long-term daily consumption of almonds also improved micronutrient profiles and eating patterns of free-living healthy individuals.The lack of weight gain was especially evident in more obese subjects, and some actually lost small amounts of weight.Food records from participants showed that almonds replaced less healthy high calorie snacks in their diets.

Frison-Norrie, S.L., P. Sporns, 2002. Identification and quantification of flavonol glycosides in almond seedcoats using MALDI-TOF MS. J Agri Food Chem. 50:2782-7.

The importance of flavonol glycosides, a subclass of flavonoids, has led to the development of a number of methods for identification and quantification.Traditionally, flavonol glycosides have been characterized using paper chromatography, thin-layer chromatography, and UV spectroscopy.Recently the application of high-performance liquid chromatography (HPLC) for their separation and quantification has become predominant.Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a new analytical technique first introduced in l987, and it offers several advantages over other methodologies including ease of sample preparation, rapid generation of spectra, tolerance of impurities, and minimal fragmentation allowing direct access to molecular weight.The objectives of the current research were to develop and validate a MALDI-TOF MS methodology for qualitative and quantitative analysis of flavonol glycosides in almond seedcoats.The four flavonol glycosides identified in almond seedcoats for the first time were:isorhamnetin rutinoside, isohamnetin glucoside, kaempferol rutinoside, and kaempferol glucoside.

Frison-Norrie, S.L., P. Sporns, 2002. Variation in the flavonol glycoside composition of almond seedcoats as determined by MALDI-TOF Mass Spectrometry. J Agric Food Chem. 50:6818-22.

Seedcoats of 16 almond varieties were screened for flavonol glycosides.Each of the 16 seedcoat samples exhibited a unique composition.In all almond varieties, isorhamnetin rutinoside was the most abundant flavonol glycoside, and the total content ranged from 75 to 250 mg/g.

Fulgoni, V.L., M. Abbey, P. Davis, D. Hyson, D. Jenkins, J. Lovejoy, M. Most, J. Sabaté, G. Spiller, 2002.Almonds lower blood cholesterol and LDL-cholesterol but not HDL-cholesterol or triglycerides in human subjects: results of a meta-analysis. FASEB J. 16(5): A981.

A meta-analysis of seven studies was conducted to determine the effects of almond consumption on blood total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C) and triglycerides (TG).Data from 146 individuals with normal, mild or moderate hypercholesterolemia were included in the meta-analysis.The results showed that almonds significantly reduced TC and LDL-C with no effect on HDL-C or TG.

Hyson, D., B.O. Schneeman, P.A. Davis, 2002. Almonds and almond oil have similar effects on plasma lipids and LDL oxidation in healthy men and women. J Nutr. 132(4):703-7.

Scientists compared the effects of whole almonds vs. almond oil consumption on plasma lipids and reduced cardiovascular risk in healthy men and women.They found that with either whole almonds or almond oil there was a 54% increase in monounsaturated fat in diet, decreased saturated fat and cholesterol intake, and no significant changes in total energy, total or polyunsaturated fat intake.They concluded that whole almonds and almond oil did not differ in their beneficial effects suggesting that the favorable effect is due to components in the almond oil fraction.

Jaceldo-Siegl, G.E. Fraser, J. Sabaté, 2001.Effect of almond supplementation on eating patterns, and micronutrient and fatty acid intake profile in free-living healthy adults. Ann Nutr Metab. 45(1):152.

In this study, long-term daily consumption of almonds improved the fatty acid and micronutrient profile, and eating patterns of free-living healthy individuals.The researchers concluded that regular nut intake can be considered as part of a nutrition-related behavior change to improve cardiovascular health in adults.

Jaceldo-Siegl, K., J. Sabaté, S. Rajaram, G.E. Fraser, 2004.Long-term almond supplementation without advice on food replacement induces favourable modifications to the habitual diets of free-living individuals. Brit J of Nutr. 92:533-40.

This study evaluated the impact of long-term daily almond supplementation in 81 healthy men and women, aged 25-70 years, on nutrient profile and nutrient displacement. Subjects were followed for one year.During the first 6 months they followed their habitual diet; in the next 6 months they supplemented with approximately 52 g/day of almonds (about 42 nuts). Diets were assessed via 7, 24-hr. telephone recalls in each diet period. The intakes of MUFA, PUFA, fiber, vegetable protein, alpha-tocopherol, copper and magnesium increased significantly by 42, 24, 12, 19, 66, 15, and 23% respectively, when subjects changed from their habitual diets to the almond-supplemented diet.The intakes of trans fatty acids, animal protein, sodium, cholesterol and sugars significantly decreased by 14, 9, 21, 17 and 13% respectively during the same time period.These nutrient changes correspond with the recommended dietary changes to prevent cardiovascular and other chronic diseases.The authors concluded that a daily supplement of almonds can result in favorable nutrient modifications to an individual’s habitual diet for chronic disease prevention.

Jambazian, P. R, E. Haddad, S. Rajaram, J. Tanzman, J. Sabaté, 2005. Almonds in the Diet Simultaneously Improve Plasma Alpha-Tocopherol Concentrations and Reduce Plasma Lipids. J. Am. Diet. Assoc. 105:449-454.

The study objective was to assess the dose response effect of almond intake on plasma and red blood cell tocopherol concentrations in healthy adults while enrolled in a randomized crossover feeding trial. Participants were 16 men and women, aged 41 +/- 13 years. Incorporating almonds into the diet helped meet the revised Recommended Dietary Allowance of 15 mg/day alpha tocopherol and increased lipid adjusted plasma and red blood cell alpha tocopherol concentrations in a dose response fashion. The USDA recommended serving size of one ounce of almonds daily can be isocalorically substituted for while bread, crackers, chips and similar refined products to provide 7.4 mg alpha tocopherol vitamin E.

Jenkins, D.J.A., C.W.C. Kendall, A. Marchie, D. Faulkner, J.M.W. Wong, R. de Souza, A. Emam, T.L. Parker, E. Vidgen, E.A. Trautwein, K.G Lapsley, R.G. Josse, L.A. Leiter, W. Singer, P.W. Connelly, 2005. Direct comparison of a dietary portfolio of cholesterol-lowering foods with a statin in hypercholesterolemic partipants. Am J Clin Nutr. 81:380-387.

In phase 3 34 men and women underwent all 3 1-month treatments in random order as outpatients: a very low-saturated fat diet (control diet); the same diet with 20 mg lovastatin (statin diet); and a diet high in plant sterols (1.0 g/1000 kcal), soy protein foods (including soy milks and soy burgers, 21.4 g/1000 kcal), almonds (14 g/1000 kcal), and viscous fibers from oats, barley, psyllium, and the vegetables okra and eggplant (10 g/1000 kcal) (portfolio diet). Fasting blood samples were obtained at weeks 0, 2 and 4. LDL-cholesterol concentrations decreased by 8.5 ± 1.9%, 33.3 ± 1.9%, and 29.6 ± 1.3% after 4 weeks of the control, statin and portfolio diets, respectively. Although the absolute difference between the statin and the portfolio treatments was significant at 4 weeks (P = 0.013), 9 participants (26%) achieved their lowest LDL-cholesterol concentrations with the portfolio diet. Moreover, the statin (n = 27) and the portfolio (n = 24) diets did not differ significantly (P = 0.288) in their ability to reduce LDL cholesterol below the 3.4-mmol/L primary prevention cutoff.

Jenkins, D.J.A., C.W.C. Kendall, D. Faulkner, E. Vidgen, E.A. Trautwein, T.L. Parker, A. Marchie, G. Koumbridis, K.G. Lapsley, R.G. Josse, L.A. Leiter, P.W. Connelly, 2002.A dietary portfolio approach to cholesterol reduction: combined effects of plant sterols, vegetable proteins and viscous fibers in hypercholesterolemia. Metabolism. 51:1596-1604.

This seven-week pilot study with 13 men and women was the first of its kind to examine the combined effect of a “portfolio” of foods with heart-health related claims—almonds as well as foods high in soy protein, viscous fiber and plant sterols.The plan, whose hypothesis is that combining foods with cholesterol-lowering properties into one diet will work in synergy resulting in greater reductions in “bad” cholesterol, reduced LDL cholesterol by 29% and the ratio of LDL cholesterol to HDL cholesterol by 26%.Results were so encouraging that the researchers developed a multi-phase research plan.

Jenkins, D.J.A., C.W.C Kendall, A. Marchie, D. Faulkner, E. Vidgen, K.G. Lapsley, E.A. Trautwein, T.L. Parker, R.G. Josse, L.A. Leiter, P.W. Connelly, 2003.The effect of combining plant sterols, soy protein, viscous fibers, and almonds in treating hypercholesterolemia. Metabolism. 52:11:1478-83.

In this second phase of the portfolio approach to lowering cholesterol a control arm was added, which was the National Cholesterol Education Program’s Step 2 diet.There were 23 subjects tested for a one-month, randomized controlled parallel study.The LDL and the LDL:HDL-cholesterol ratio were both significantly lower on the portfolio diet than on the control diet.Mean weight loss was similar on the test and control diets, and no difference was seen in blood pressure, HDL-C, serum triglycerides, lipoprotein, or homocysteine concentrations between diets.

Jenkins, D.J.A., C.W.C. Kendall, A. Marchie, D. Faulkner, J.M.W. Wong, R. de Souza, A. Emam, T.L. Parker, E. Vidgen, K.G. Lapsley, E.A. Trautwein, R.G. Josse, L.A. Leiter, P.W. Connelly, 2003. Effects of a dietary portfolio of cholesterol-lowering foods vs. lovastatin on serum lipids and c-reactive protein. JAMA. 290:502-10.

The study directly compared three randomized groups of patients with high cholesterol.One group of 16 people ate the National Cholesterol Education Program’s Step 2 diet, which is a very low-saturated fat diet based on whole-wheat cereals and low-fat dairy foods. Another group of 14 people ate this same diet in addition to taking a 20-milligram lovastatin, a cholesterol-lowering drug, each day.A third group of 16 ate the portfolio diet high in almonds and other foods high in plant sterols and vegetable protein as well as viscous fiber.The control, statin and dietary portfolio had mean decreases in low-density lipoprotein cholesterol of 8.0%, 30.9% and 28.6%, respectively.Respective reductions in c-reactive protein were 10.0%, 33.3% and 28.2%. This study found that patients on the portfolio diet were the first documented to lower their c-reactive protein levels through dietary intervention.C-reactive protein is an indication of inflamed arteries and a risk factor for heart disease.

Jenkins, D.J., C.W. Kendall, A. Marchie,T.L. Parker, P.W. Connelly, W. Qian, J.S. Haight, D. Faulkner, E. Vidgen, K.G. Lapsley, G.A. Spiller. 2002. Dose response of almonds on coronary heart disease risk factors: blood lipids, oxidized low-density lipoproteins, lipoprotein (a), homocysteine, and pulmonary nitric oxide: a randomized, controlled, crossover trial. Circulation 106(11):1327-32.

Researchers found that patients with high cholesterol who ate about one ounce of almonds each day lowered their LDL (low density lipoprotein) cholesterol at least 3%.There was an even greater decrease for those who ate about two handfuls of almonds per day, indicating that there is a dose response effect.According to the authors, almonds reduced coronary heart disease risk factors in a dose-dependent manner and may be used as healthy snacks without weight gain.

Jia, X., N. Li, W. Zhang, X. Zhang, K. Lapsley, G. Huang, J. Blumberg, G. Ma, and J. Chen, 2006. A pilot study on the effects of almond consumption on DNA damage and oxidative stress in smokers. Nutrition and Cancer. 54(2), 179-83.

This pilot study looked at the effects of almond consumption on DNA damage and oxidative stress among 30 healthy adult male regular smokers. The subjects were randomly divided into three groups. Group A (control group) did not receive any almonds. Subjects in Groups B and C received 3 oz and 6 oz (84 g and 168 g) of almonds each day respectively for 4 wk. Two known biomarkers for DNA damage, urinary 8-hydroxy- 2'-deoxyguanosine (8-OH-dG) and single strand DNA breaks of peripheral blood lymphocytes, were measured by enzyme-linked immunosorbent assay and comet assay, respectively. In addition, plasma malondialdehyde (MDA) level, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were measured as biomarkers for oxidative stress. The results showed lower levels of urinary 8-OH-dG and single strand DNA breaks in the two almond-treated groups as compared with the control group. Furthermore, MDA levels in the almond-treated groups were lower than the controls. However, no significant effects of almonds on SOD and GSH-PX activities were found. The results indicated that almond consumption has preventive effects on oxidative stress and DNA damage caused by smoking, but a larger, randomized, placebo-controlled clinical trial on almonds will be initiated in the near future.

Kendall, C.W.C., D.J.A. Jenkins, A. Marchie, Y. Ren, P.R. Ellis, K.G. Lapsley, 2003.Energy availability from almonds: implications for weight loss and cardiovascular health.A randomized controlled dose-response trial. FASEB Journal. 17(4):A339.

Twenty-seven hyperlipidemic men and women consumed three iso-energetic (mean 423 kcal/day) supplements consisting of full-dose almonds (50-100g/d), half-dose almonds with half-dose muffins, and full-dose muffins, each for one month in a randomized controlled crossover study. The results showed that almond consumption improved blood lipid risk factors for CHD in a dose-dependent manner without weight gain.It appears that a portion of energy from almonds is unavailable because the cell walls act as a physical barrier to gastrointestinal digestion of nutrients.

Lamarche, B., S. Desroches, D.J.A. Jenkins, C.W.C. Kendall, A. Marchie, D. Faulker, E. Vidgen, K.G. Lapsley, E. Trautwein, T. Parker, R. Josse, L. A. Leiterm P. W. Connelly, 2004. Combined effects of a dietary portfolio of plant sterols, vegetable protein, viscous fibre and almonds on LDL particle size. Brit J Nutr. 92:657-63.

Small dense LDL particles have been associated with an increase for CVD. In this study 12 patients with mildly elevated plasma LDL-cholesterol levels were placed on the portfolio eating plan for one month. Fasting blood lipids were obtained at the start and at 2-week intervals. The diet induced reductions on plasma LDL cholesterol of 30% was attributed to the concurrent reductions in large (30%), medium (29%) and small (21%) LDL particles. These results indicate that the combination of these foods and dietary components are effective in reducing CVD risk and serum concentrations of all LDL fractions, including small dense LDL.

Lapsley, K.G., G. Huang, 2004. Health Benefits of Almonds. Cereal Foods World. 49:1: 6-10.

This overview focuses first on the nutrition research linking almonds and heart health whether as a single food within a dose-response study (with a cholesterol lowering effect of approximately 5%) or in a dietary portfolio of other foods with proven heart health benefits (where there are combined cholesterol lowering effects of up to 30%). The emerging research that almonds as a nutrient-rich, satiating food may have a role to play in weight control and maintenance is reviewed next, followed by the latest information on almond phytochemicals and their potential role in cancer prevention. The article ends with a description of the California almond industry and the almond varieties grown and their uses.

Lovejoy, J. C., M.M. Most, M. Lefevre, F.L. Greenway, J.C. Reed, 2002. Effect of diets enriched in almonds on insulin action and serum lipids in adults with normal glucose tolerance or type 2 diabetes. J Nutr. 76(5):1000-6.

Results from this study suggest that almonds have no effect on insulin sensitivity in healthy adults nor do they affect glycemia in Type 2 diabetics.The researchers did find that almonds had beneficial effects on serum lipids in these patients.

Milbury, P. E., C.-Y. Chen, G. G. Dolnikowski, J. B. Blumberg, 2006. Determination of flavonoids and phenolics and their distribution in almonds. J Agr Food Chem - in press; publication date 6/28/06.

Limited information is available concerning the qualitative and quantitative composition of polyphenolic compounds, especially flavonoids, in almonds. The total phenols, flavonoids and phenolic acids in California almond (Prunus dulcis) skins and kernels among the principal almond varieties (Butte, Carmel, Fritz, Mission, Monterey, Nonpareil, Padre and Price) with high-performance liquid chromatography (HPLD)/electrochemical detection and UV detection were determined. Liquid chromatography/tandem mass spectrometry under identical HPLC conditions was utilized to verify identities of the predominant flavonoids and phenolic acids. Total phenols ranged from 127 (Fritz) to 241 (Padre) mg gallic acid equivalents/100g of fresh weight. The analyses were compiled to produce a data set of 18 flavonoids and three phenolic acids. Using the existing approach of calculating only the aglycone form of flavonoids for use in the U.S. Department of Agriculture nutrient database, whole almonds would provide the most prevalent aglycones of isorhamnetin at 17.31 (4.91), kaempferol at 12.21 (0.35), catechin at 1.93 (0.55), quercetin at 0.04 (0.27), and epicatechin at 0.85 (0.24) mg/100g of fresh weight (mg/oz serving), respectively. These data can lead to a better understanding of the mechanisms of action underlying the relationship between almond consumption and health-related outcomes and provide values for whole and balanced almonds suitable for inclusion in nutrient databases. This approach allows for comparisons of flavonoid intake from different foods, e.g., on a weight basis, showing that almonds provide similar amount of flavonols as red onions, but 9-fold more isorhamnetin than white onions. The kaempferol and quercetin contents of almonds are comparable to that of broccoli and its concentrations of catechin is between that of brewed black and green tea.

Milbury, P., C.-Y. Chen, K\H.-K. Kwak, J. Blumberg, 2002.Almond skins polyphenolics act synergistically with α-tocopherol to increase the resistance of low-density lipoproteins to oxidation. Free Radical Research. 36(suppl. 1):78-80.

In this study, researchers found that the nutrients in almonds work together as a package to produce a greater health-promoting effect than from individual nutrients consumed alone.Their emerging evidence indicates that the unique combination of almond skins keep LDL cholesterol from oxidizing, a mechanism associated with the formation of plaque in arteries of the heart.Even at very low levels, when the almond skins compounds combine with the vitamin E in the almonds and vitamin C from other foods, they act in synergy and play a co-defensive role against atherosclerosis--in a fashion where the sum of their actions is much greater than each part.

Ren, Y, K.W. Waldron, J.F. Pacy, P.R. Ellis, 2001.Chemical and histochemical characterization of cell wall polysaccharides in almond seeds in relation to lipid bioavailability. Biologically-active phytochemicals in food, (ed.) W. Pfannhauser, G.R. Fenwick & S. Khokhar, Royal Soc. of Chem., Cambridge, U.K. 448-452.

The research team reported that almond cell walls may prevent the body’s absorption of all the fat present in almonds.Normal chewing of almonds breaks down only some of the cell walls, leaving others intact.Thus, not all the fat was available for digestion.

Roux, K.H., S.S. Teuber, J.M. Robotham, S.K. Sathe, 2001. Detection and stability of the major almond allergen in foods. J Agric Food Chem. 49:2131-6.

Almond major protein (AMP or amandin), the primary storage protein in almonds is the major allergen recognized by almond-allergic patients. This study showed that AMP is also an excellent marker protein for detecting trace amounts of almond in food.

Sabaté, J., E. Haddad, 2001. Almond-rich diets simultaneously improve plasma lipoproteins and alpha-tocopherol levels in men and women. Ann Nutr Metab. 45(1):596.

Researchers examined the effect of eating almonds on blood lipids, particularly on the levels of the powerful antioxidant vitamin E in the blood.According to the authors, this study shows that a natural source of vitamin E, almonds, is efficiently utilized by the body.Moreover, surveys show that on average men need 5 mg of alpha-tocopherol, and women need 8 mg of alpha-tocopherol a day to meet their vitamin E needs.Just an ounce of almonds a day can effectively close the gap on vitamin E consumption.

Sabaté, J., E. Haddad, J.S. Tanzman, P. Jambazian, S. Rajaram, 2003. Serum lipid response to the graduated enrichment of a step 1 diet with almonds: a randomized feeding trial. Am J Clin Nut. 77(6):1379-84.

Researchers compared the dose response effects for 25 healthy individuals who consumed low or high almond doses with those following the National Cholesterol Education Program’s Step 1 Diet.In a randomized crossover design, subjects were fed three isoenergetic diets for four weeks each after being fed a two-week run-in diet (containing 34% of energy from fat).All meals were prepared, weighed, and consumed at the test facility.The experimental diets included a Step 1 diet, a low-almond diet, and a high-almond diet, in which almonds contributed 0%, 10% and 20% of total energy, respectively, or about one to two handfuls of almonds.

The results showed a decrease in total cholesterol, as well as LDL or “bad” cholesterol levels across all diets--with a 4.4% reduction in total cholesterol compared to the Step 1 Diet.However, the most significant changes were seen among individuals consuming the diet with the most almonds.Individuals with normal cholesterol levels also benefited from this eating plan by maintaining healthy cholesterol levels.

Sang, S., H. Kikuzaki, K. Lapsley, R.T. Rosen, N. Nakatani, C.-T. Ho, 2002. Sphingolipid and other constituents from almond nuts (Prunus amygdalus Batsch). J Agric Food Chem. 50:4709-12.

A sphingolipid compound was isolated from almonds for the first time.Four other compounds: B-sitosterol, dancosterol, uridine, and adenosine were also isolated.

Sang, S., K. Lapsley, X. Cheng, H.-Y. Fu, D.-E. Shieh, N. Bai, R.T. Rosen, R.E. Stark, C.-T. Ho, 2002. New type sesquiterpene lactone from almond hulls (Prunus amygdalus Batch). Tetrahedron Letters. 43:2547-9.

An unusual sesquiterpene lactone, named amygdalactone, was isolated from almond hulls for the first time.This class of compounds is comprised of natural products with known anti-carcinogenic properties.

Sang, S., K. Lapsley, W.S. Jeong, P.A. Lachance, R.T. Rosen, C.T. Ho, 2002. Antioxidative phenolic compounds isolated from almond skin (Prunus amygdalus Batsch). J Agric Food Chem. 50:2459-63.

Nine phenolic compounds were isolated from the ethyl acetate and n-butanol fractions of almond skins for the first time on the basis of NMR and MS data.Several showed strong radical scavenging activity.

Sang, S., K. Lapsley, R.T. Rosen, C.T. Ho, 2002.New prenylated benzoic acid and other constituents from almond hulls (Prunus amygdalus Batsch). J Agric Food Chem. 50:607-9.

One new prenylated benzoic acid derivative and three known constituents (catechin, protocatechuic acid and ursolic acid) have been isolated from almond hulls for the first time.Each of these compounds have known antioxidant activity, which might be beneficial since the current major use of almond hulls is as cattle feed.

Sang, S., G. Li, S. Tian, K. Lapsley, R.E. Stark, R.K. Pandey, R.T. Rosen, C.T. Ho, 2002.An unusual diterpene glycoside from the nuts of almond (Prunus amygdalus Batsch). Tetrahedron Letters. 44:1199-1202.

A new unusual diterpene glycoside, named amygdaloside, was isolated from almonds.Since this family of compounds is known to have anti-tumor and anti-inflammatory effects, further research is needed in this area.

Sathe, S.K., 1993. Solubilization, electorphoretic characterization and in vitro digestibility of almond (Prunus amygdalus) proteins. J Food Biochem. 16:249-64.

The six major varieties of California almonds were fully characterized for moisture, protein, fat and ash. Two fatty acids, oleic and linoleic, accounted for up to 90% of the total fat. Over 95% of almond proteins were water soluble with a minimum solubility at ph less than 4.

Sathe, S.K., S.S. Teuber, T.M. Gradziel, K.H. Roux, 2001. Electrophoretic and immunological analyses of almond (Prunus dulcis L.) genotypes and hybrids. J Agric and Food Chem. 49(4): 2043-52.

Aqueous extracts from 60 almond samples were analyzed for protein and peptide content.A single major storage protein (almond major protein--AMP or amandin) dominated the total soluble protein composition.In addition to AMP, several minor polypeptides were present in all genotypes and variability was evident.AMP was recognized by human IgE and rabbit polyclonal antibodies in all genotypes tested, indicating AMP is an excellent allergy relevant target molecule for the purpose of detecting the presence of almonds.

Sathe, S.K., W.J. Wolf, K.H. Roux, S.S. Teuber, M. Venkatachalam, K.W.C. Sze-Tao, 2002.Biochemical characterization of amandin, the major storage protein in almond (Prunus dulcis L.). J of Agric Food Chem. 50(15):4333-41.

The major almond storage protein, amandin, was characterized by several methods for molecular weight distribution.Regardless of preparation method, all amandins are antigenically related and suitable for purposes of detecting almonds using ELISA procedures.

Spiller, G.A., D.A.J. Jenkins, O. Bosello, J.E. Gates, L.N. Cragen, B. Bruce, 1998.Nuts and plasma lipids: an almond-based diet lowers LDL-C while preserving HDL-C. J Am Coll Nutr. 17(3):285-90.

This study involved 45 hypercholesterolemic adults in a randomized, controlled, parallel study that lasted four weeks (following one week on a baseline diet).The control group consumed a diet of whole and unrefined foods plus 85g/day of cheddar cheese, 28g/day of butter, and 21g/day of rye crackers.The olive oil group consumed a base diet of whole and unrefined foods plus 48g/day of olive oil, 113g/day of cottage cheese and 21g/day of rye crackers.The almond group consumed the same base diet of whole and unrefined foods plus 100g/day of raw, unblanched almonds (both whole and ground).The almond diet lowered total cholesterol by 12% and LDL by 15% compared to baseline values, while the olive oil diet had no significant effects.

Spiller, G.A., D.J. Jenkins, L.N. Cragen, J.E. Gates, O. Bosella, K. Berra, C. Rudd, M. Stevenson, R. Superko, 1992.Effect of a diet high in monounsaturated fat from almonds on plasma cholesterol and lipoproteins. J Am Coll Nutr. 11(2):126-30.

The first study published in 1992 on almond research was a consecutive, supplemental field study involving 26 hypercholesterolemic adults that examined the effect of almonds on serum lipids as part of a low saturated fatty acid (SFA), low cholesterol, high-fiber diet.The study consisted of a two-week baseline period followed by a nine-week intervention period.The baseline diet was comprised mainly of grains, beans, vegetables, fruit and low-fat milk products.Meat, fatty fish, high-fat milk products, eggs and SFA were limited.The almond diet consisted of the baseline diet with the addition of 100g/d of raw almonds that supplied 34g/d of monounsaturated fatty acids (MUFA), 12g/d of (polyunsaturated fatty acids (PUFA), and 6g/d of SFA. Almond oil was the only oil allowed for food preparation.There was a rapid and sustained reduction in LDL without changes in HDL.Total cholesterol was decreased by 9% and LDL was decreased by 12% compared to baseline values.There were no significant changes in HDL or triglycerides.

Spiller, G.A., A. Miller, K. Olivera, J. Reynolds, B. Miller, S.J. Morse, A. Dewell, J.W. Farquhar, 2003.Effects of plant-based diets high in raw or roasted almonds, or roasted almond butter on serum lipoproteins in humans. J Am Coll Nutr. 22(3):195-200.

This study compared the lipid-altering effect of roasted salted almonds and roasted almond butter with that of raw almonds,as part of a plant-based diet in 38 free-living, hypercholesterolemic men and women (n = 26) with a mean total serum cholesterol (TC) of 245 + 29 mg/dL (mean + SD).All three forms of almonds in the context of a heart-healthydiet significantly lowered low-density lipoprotein-cholesterol(LDL) from baseline to the completion of the study. Both rawand roasted almonds significantly lowered TC, whereas the decreaseby almond butter (in a smaller cohort) did not reach statisticalsignificance. High-density lipoprotein-cholesterol (HDL) didnot significantly change with raw or roasted almonds but slightlyincreased with almond butter. At the end of the study, bloodpressure did not change significantly from baseline values forany of the groups. These results suggest that unblanched almonds—whetherraw, dry roasted, or in roasted butter form—can play aneffective role in cholesterol-lowering, plant-based diets.

Sriwardahana, S.S.K.W., F. Shahidi, 2002.Antiradical activity of extracts of almond and its by-products. J Am Oil Chem Soc. 79(9):903-8.

Antioxidant activities of ethanolic extracts of whole almonds, almond skins and hulls were evaluated using different free radical trapping assays.Total antioxidant capacities of skins and hulls were over ten times greater than almonds.

Sze-Tao, K.W.C., S.K. Sathe, 2000. Functional properties and in vitro digestibility of almond (Prunus dulcis L.) protein isolate. Food Chem. 69:153-60.

Almond protein isolates (API) solutions were less viscous than those of soy protein isolates. Foaming and oil absorption capacities were comparable. Emulsion activity index was significantly higher. API was easily hydrolyzed by pepsin in vitro.

Venkarachalam, M., S.S. Teuber, K.H. Roux, S.K. Sathe, 2002.Effects of roasting, blanching, autoclaving, and microwave heating on antigenicity of almonds. J Agric Food Chem. 50(12):35448.

These researchers have characterized the major storage proteins of almonds, which cause allergic reactions in approximately one percent of the U.S. population.Their most recent research focused on the effects of processing on various forms of almonds and how to reduce almond allergenicity.

Wien, M.A., J.M. Sabaté, D.N. Ikle, S.E. Cole, and F.R. Kandeel, 2003.Almonds vs. complex carbohydrates in a weight reduction program. Intl J Obesity. 27:1365-72.

A moderate-fat diet with almonds resulted in more weight loss than a low-fat diet in a six-month study, even though the total number of calories was the same for both groups.Researchers concluded that there may be qualities in almonds which helped the first group lose more weight.According to the authors, since a side effect of some diabetes medication is increased hunger, the faster one can get off of medications during weight loss, the better, because when you take away something creating hunger behind the scenes, it can lead to greater success in the weight-loss effort.

Wolf, W.J., S.K. Sathe, 1998. Ultracentrifugal and polyacrylamide gel electrophoretic studies of extractability and stability of almond meal proteins. J Sci Food Agric. 78:511-21.

Solubility and stability properties of almond proteins were determined to gain a better insight into the complexity of these proteins.The 14S amandin fraction constitutes 65-70% of the extractable proteins.

Xiao, Y., J.B. Wang, S.F. Yan, X.J. Lian, Y. Tang, Y. Liu, 2002.Effect of nut rich in monounsaturated fatty acid on serum lipids in hyperlipidemia patients.J of China Pub Health. 18(8):931-2.

Researchers at Peking Medical University studied 85 Chinese hyperlipemic patients.After a four-week experimental phase, with patients eating 75g (over 2 oz.) of almonds daily, total cholesterol and apolipoprotein B decreased significantly.

Zemaitis, J., J. Sabaté, 2001.Effect of almond consumption on stool weight and stool fat. FASEB J. 15:A602, Abstract #483.7.

This study looked at the effect of a diet rich in almonds on stool weight and stool fat content in 9 healthy men and women (5 women and 4 men). The subjects were fed an almond-free diet (control diet), a low almond diet (10% energy from almonds) and a high almond diet (20% energy from almonds). The absolute and relative increase excretion of stool fat while on the almond diets may have resulted from lower levels of fat absorption due to the structure of lipid storing granules in nuts or to various nut fiber components.

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HAZELNUT REFERENCES

Alphan, E., M. Pala, F. Ackurt, T. Yilmaz, 1997.Nutritional composition of hazelnuts and its effects on glucose and lipid metabolism. In: Kosal AI, Oky Y, Gunes NT, eds. Proceedings of the Fourth International Symposium on Hazelnut. Acta Hort. 445:305-10.

Durak, I., I. Koksal, M. Kacmaz, S. Buyukkocak, B.M. Cimen, H.S. Ozturk, 1999.Hazelnut supplementation enhances plasma antioxidant potential and lowers plasma cholesterol levels. [Letter to the Editor].Clin Chim Acta. 284(1):113-5.

In this study, 30 healthy medical students added 1 gram of hazelnuts per kilogram of body weight per day to their normal daily diet for 30 days.Total cholesterol was lowered by 6%, LDL by 19%, while HDL increased 7% and triglycerides 25% compared to baseline values.Plasma antioxidant potential (AOP) also increased by 20%.

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MACADAMIA REFERENCES

Colquhoun, D.M., J.A. Humphries, D. Moores, S.M. Somerset, 1996. Effects of a macadamia nut enriched diet on serum lipids and lipoproteins compared to a low fat diet. Food Australia. 48(5):216-22.

Curb, J.D., G. Wergowske, J.C. Dobbs, R.D. Abbott, B. Huang, 2000. Serum lipid effects of a high-monounsaturated fat diet based on macadamia nuts. Arch Intern Med. 160(8):1154-8.

This study involved 30 subjects who consumed three different diets each for 30 days.The first diet was a typical American diet (AM), high in saturated fat, the second diet was the American Heart Association (AHA) Step 1 diet and the third diet was a macadamia based diet (MAC) high in monounsaturated fatty acids.Compared to the AM diet, the MAC diet lowered total cholesterol, LDL and HDL each by 5% and triglycerides by 10%.The AHA diet had similar results except for an 8% increase in triglycerides.

M. L. Garg, P. Rudra, R. Blake, R. Wills, 2003. Macadamia nut consumption lowers plasma cholesterol levels in hypercholesterolemic men. J Nutr. 133:1060-3.

This study assessed the cholesterol-lowering potential of macadamia nuts in 17 hypercholesterolemic men.The subjects were given 40-90g/d macadamia nuts—the equivalent to 15% energy intake for 4 weeks.At the end of the study, total cholesterol and LDL-cholesterol levels decreased by 3.0 and 5.3% respectively, and HDL-cholesterol levels increased by 7.9%. According to the authors, “This study demonstrates that macadamia nut consumption as part of a healthy diet favorably modifies the plasma lipid profile in hypercholesterolemic men despite their being high in fat.

Hiraoka-Yamamoto, J., K. Ikeda, H. Negishi, M. Mori, A. Hirose, S. Sawada, K. Kitamori, Y. Onobayashi, S. Kitano, M. Tashiro, T. Miki, Y. Yamori, 2004. Serum lipid effects of a monounsaturated (palmitoleic) fatty acid-rich diet based on macadamia nuts in healthy, young Japanese women. Clinical and Experimental Pharmacology and Physiology. 31:S37–S38.

Recent studies have identified potential beneficial effects of eating nuts, most of which have substantial amounts of monounsaturated fatty acids (MUFA). Macadamia nuts consist of 75% fat by weight, 80% of which is MUFA (palmitoleic acid). To examine variations in serum lipid levels in response to a high-MUFA diet based on macadamia nuts, 3 week interventions of macadamia nuts, coconuts and butter were determined in young, healthy Japanese female students. After 3 weeks intervention, serum concentrations of total cholesterol and low-density lipoprotein–cholesterol were significantly decreased in the macadamia nut and coconut diets and bodyweight and body mass index were decreased in the group fed macadamia nuts, although there were no statistically significant changes in the group fed butter.

Kaijser, A., P. Dutta, G. Savage, 2000. Oxidative stability and lipid composition of macadamia nuts grown in New Zealand. Food Chemistry. 71:67-70.

This study looked at the parameters which might influence the stability and storage characteristics of some selected cultivars of macadamia nuts grown in New Zealand. Four cultivars of macadamia nuts (Macadamia tetraphylla) were harvested from the North Island of New Zealand during 1997. Total lipids, composition of fatty acids, tocopherols, sterols and stability of oils, were determined on the oil extracted from the fresh nuts. The total lipid content of the nuts ranged from 69 to 78%, while the stability of the oil measured by Rancimat test ranged from 3.6 to 19.8 h. Peroxide values of the fresh oil ranged from 0.56 to 3.61 meq O2/kg oil. The major fatty acids were oleic acid, palmitoleic acid and palmitic acid; oleic acid accounted for 40.6 to 59% of the total fatty acids. The polyunsaturated fatty acid content was low, ranging from 3.0 to 4.7%. a-Tocopherol and d-tocopherol were the only two tocopherols identified in the extracted oil. The major sterols identified were sitosterol, Δ5-avenasterol, campesterol and stigmasterol.

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PECAN REFERENCES

Haddad, E., P. Jambazian, M. Karunia, J. Tanzman, J. Sabaté, 2006. A pecan-enriched diet increases tocopherol/cholesterol and decreases thiobarbituric acid reactive substances in plasma of adults. Nutrition Research. 26:397-402.

This randomized, controlled, cross-over feeding study looked at the effect of a pecan-rich diet on plasma and tocopherol concentrations on measures of antioxidant capacity and lipid peroxidation in 24 healthy persons. The subjects were assigned to 2 diets, each for 4 weeks: a control diet and a pecan-enriched (20% of calories) diet. Cholesterol-adjusted plasma tocopherol increased by 10.1%, a-tocopherol decreased by 4.6%, and malondialdehyde concentrations measured as thiobarbituric acid reactive substances decreased by 7.4% on the pecan diet. These data provide some evidence for potential protective effects of pecan consumption in healthy individuals.

Morgan, W.A., B.J. Clayshulte, 2000.Pecans lower low-density lipoprotein cholesterol in people with normal lipid levels. J Am Diet Assoc. 100(3):312-8.

A randomized, controlled, parallel study involved 19 healthy adults who followed either a control diet (no nuts) or a pecan diet which included 68 grams of pecans per day (with no additional nuts).After eight weeks, those following the pecan diet had a 6% decrease in LDL compared to the baseline value.Effects on total cholesterol, HDL and triglycerides were not significant.

Rajaram, S., K. Burke, B. Connell, T. Myint, J. Sabaté, 2001.A monounsaturated fatty acid-rich pecan enriched diet favorably alters the serum lipid profile of healthy men and women. J Nutr. 131:2275.

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PISTACHIO REFERENCES

Edwards, K., I. Kwaw, J. Matud, Kurtz, 1999.Effect of pistachio nuts on serum lipid levels in patients with moderate hypercholesterolemia. J Am Coll Nutr. 18(3):229-32.

Ten patients with moderate hypercholesterolemia were enrolled in a controlled, randomized, crossover study for two 3-week periods.A reference diet of 37% total fat was compared to a pistachio diet of 39% total fat (66g/day of pistachios) in which 20% of the daily caloric intake was substituted with pistachios.Compared to initial values, the pistachio diet decreased total cholesterol by 2%, and increased HDL by 12%, while there was no significant effect on LDL or triglycerides.

Kocyigit, A., A.A. Koylu, H. Keles, 2006.Effects of pistachio nuts consumption on plasma lipid profile and oxidative status in healthy volunteers. Nutrition, Metabolism & Cardiovascular Diseases. 16:202-9.

This study looked at the effects of pistachio nuts consumption on plasma lipid profile and oxidative status in 24 healthy men and 20 healthy women with normal lipid levels. All subjects consumed their regular diets during a 1-week period. After this period, half of the subjects were randomized to a regular diet group and the other half were randomized to a pistachio group which involved substituting pistachio nuts for 20% of their daily caloric intake for 3 weeks. After 3 weeks, with the pistachio diet, the mean plasma total cholesterol, malondialdehyde (MDA) levels and, total cholesterol/HDL and LDL/HDL ratios were found to be significantly decreased; on the contrary, HDL and antioxidant potential (AOP) levels, and AOP/MDA ratios were significantly increased. Triglyceride and LDL levels also decreased but this was not statistically significant. These results indicate that consumption of pistachio nuts decreased oxidative stress, and improved total cholesterol and HDL levels in healthy volunteers.

Sheridan, M.J., J.N. Cooper, M. Erario, 2003. Pistachio nuts and serum lipid levels in patients with moderate hypercholesterolemia. (Submitted to AJCN)

In an 8-week cross-over trial, 15 subjects with moderate hypercholesterolemia were randomized to one of two diets after a lead-in period of one week: 20% of calories as pistachio nuts for 4 weeks followed by regular diet for 4 weeks or the reverse. On the pistachio nut diet, total fat was 48% of calories and monounsaturated fat intake was 20% of total calories in comparison to the regular diet where calories were 31% total fat and 11% monounsaturated fat.Significant reductions were seen in total/HDL cholesterol ratios (-8%,p=0.001) and LDL/HDL cholesterol ratios (-13%, p=0.004), and a significant increase was seen in HDL (6%, p=0.02). Although statistically marginal, trends in the optimal direction also were seen for total cholesterol (-4%, p=0.11), LDL-C (-9%, p=0.06) and apolipoprotein B-100 (-6%, p=0.08). No changes were seen in triglycerides or apolipoprotein A-1. No differences were seen in BMI or blood pressure.

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WALNUT REFERENCES

Almario, R.U., V. Vonghavaravat, R. Wong, S.E. Kasim-Karakas, 2001.Effects of walnut consumption on plasma fatty acids and lipoproteins in combined hyperlipidemia. Am J Clin Nutr. 74:72-9

In this study with 7 men and 16 postmenopausal women, participants sequentially adhered to the following diets in free-living conditions: (1) habitual diet, (2) habitual diet plus walnuts, (3) low-fat diet and (4) low-fat diet plus walnuts.Compared to the diets without walnuts, the proportion of small particle LDL decreased by 27% with the habitual diet plus walnuts and 7% with the low-fat diet plus walnuts.Small particle LDL is considered to be a promoter of cardiovascular disease.

Anderson et al, 2001. Walnut polyphenolics inhibit in vitro human plasma and LDL oxidation. J Nutr. 0022-3166

Polyphenol-rich extracts from walnuts were studied in vitro and compared with ellagic acid for their ability to inhibit in vitro plasma and LDL oxidation, as well as their effects on LDL during oxidative stress.

Results:Walnut polyphenolics are effective inhibitors of in vitro plasma and LDL oxidation.

Chisolm, A., J. Mann, M. Skeaff, C. Franpton, W. Sutherland, A. Duncan, S. Tiszavari, 1998.A diet rich in walnuts favorably influences plasma fatty acid profile in moderately hyperlipidemic subjects. Eur J Clin Nutr. 52:12-6.

In this randomized, crossover study with 21 male subjects, researchers found that despite an unintended increase in the total fat intake on the walnut diet, fatty acid profile of the major lipid fractions showed changes, which might be expected to reduce risk of cardiovascular disease.

Comstock, S.S., G. McGranahan, W.R. Peterson, S.S. Teuber, 2004.Extensive in vitro cross-reactivity to seed storage proteins is present among walnut (Juglans) cultivars and species. Clin Exp Allergy. 34:1583-90.

This study looked at the possibility of developing a hypoallergenic walnut using English walnut cultivars or other Juglans species that showed decreased IgE binding to major seed storage proteins or an inability to cross-react with Jug r 1 or Jug r 2 (important English walnut allergens).However, based on their findings, the researchers concluded that it is unlikely that a composite hypoallergenic walnut could be bred from available germplasm.Patients with severe allergy to English walnuts are likely to be clinically allergic to all commercial English walnut cultivars and other closely related Juglans species.

Esposito, K., R. Marfella, M. Ciotola, C. Di Palo, F. Giugliano, G. Giugliano, M. D’Armiento, F. D’Andrea, D. Giugliano, 2004.Effect of a Mediterranean-style diet on endothelial dysfunction and markers of vascular inflammation in the metabolic syndrome. JAMA. 292:1440-6.

This study looked at the effect of a Mediterranean-style diet on both endothelial function and vascular inflammatory markers in patients with metabolic syndrome.The latter has been associated with an increased risk of cardiovascular disease, yet the role of diet in metabolic syndrome is poorly understood.In a randomized, single-blind 2-year trial, 180 men and women with metabolic syndrome were assigned to two different diets. The intervention group was instructed to follow a Mediterranean-style diet that included walnuts, and the control group followed a prudent diet (50-60% carbohydrate; 15-20% protein; and total fat less than 30%).

After 2 years, the intervention group consumed more foods rich in mono- and polyunsaturated fats, fiber and had a lower ratio of omega-6 to omega-3 fatty acids.The level of physical activity increased in both groups by 60%.Mean body weight decreased more in the intervention group.High-sensitivity C-reactive protein was significantly reduced and insulin resistance was decreased compared to the control group.After 2 years of follow-up, 40 patients in the intervention group still had features of the metabolic syndrome compared to 78 patients in the control group.

Feldman, E.B., 2002.LSRO Report: The scientific evidence for a beneficial health relationship between walnuts and coronary heart disease. J Nutr. 132:1062S-101S.

Iwamoto M., K. Imaizumi, M., Sato, Y. Hirooka, K. Sakai, A. Takeshita, M. Kono. 2002. Serum lipid profiles in Japanese women and men during consumption of walnuts. Eur J Clin Nutr. 56(7):629-37.

In this 4-week controlled, single-blind crossover designed study with 40 healthy men and women, subjects were randomly assigned to two mixed natural diets.After four weeks, the groups switched diets. Researchers found that LDL cholesterol was lowered by 8.9% in men and 10.6% in women.Total cholesterol was lowered by 3.8% in men and 4.9% in women.There was no significant change in HDL cholesterol.

Lavedrine, F., D. Zmirou, A. Ravel, F. Balducci, J. Alary, 1999.Blood cholesterol and walnut consumption: a cross-sectional survey in France. Prev Med. 28(4):333-9.

In this cross-sectional study with 793 men and women, ages 18-65, researchers observed a positive effect of walnut consumption on blood HDL cholesterol and apo A1.This is of special interest since these lipid parameters have been shown to be negatively correlated with cardiovascular morbidity.

Munoz, S., M. Merlos, D. Zambon, C. Rodriguez, J. Sabaté, E. Ros, J.C. Laguna, 2001.Walnut-enriched diet increases the association of LDL from hypercholesterolemic men with human HepG2 cells. J Lipid Res. 42(12):2069-76.

In this randomized, crossover feeding trial, 10 hypercholesterolemic men followed a control, Mediterranean-type cholesterol-lowering diet, and a diet of similar composition in which walnuts replaced 35% of energy from unsaturated fat.Each diet was followed for six weeks. The walnut diet reduced serum total and LDL cholesterol by 4.2% and 6.0% respectively.

Ros, E., I. Núñez, A. Pérez-Heras, M. Serra, R. Gilabert, E. Casals, R. Deulofeu, 2004.A walnut diet improves endothelial function in hypercholesterolemic subjects. Circulation. 109:1609-14.

To determine whether or not walnut intake would reverse endothelial dysfunction, researchers randomized 21 hypercholesterolemic men and women (ages 25-75) to a cholesterol-lowering Mediterranean diet, and a diet of similar energy and fat content in which approximately 1.4-2.3 ounces of walnuts daily replaced roughly 32 percent of the energy from monounsaturated fat. Participants followed each diet for four weeks.At the end of the study researchers observed that substituting walnuts for monounsaturated fat in a Mediterranean diet improved endothelium-dependent vasodilatation in individuals with high cholesterol levels.

Sabaté, J., G.E. Fraser, K. Burke, S.F. Knutsen, H. Bennett, K.D. Lindsted, 1993.Effects of walnuts on serum lipid levels and blood pressure in normal men. NEJM. 328(9):603-7.

In this 8-week randomized crossover feeding study, researchers compared the Step 1 Diet of the National Cholesterol Education Program, recommended by the American Heart Association, and a walnut diet (walnuts substituted for some of the saturated fat in the diet).In the walnut diet, LDL cholesterol dropped 16% and total cholesterol dropped 12%, out-performing the Step 1 control diet.

Tapsell, L.C., L.J. Gillen, C.S. Patch, M. Batterham, A. Owen, M. Baré, M. Kennedy, 2004. Including walnuts in a low-fat/modified-fat diet improves HDL cholesterol-to-total cholesterol ratios in patients with Type 2 diabetes. Diabetes Care. 27:2777-83.

This parallel randomized controlled trial compared three different diets, each containing 30% calories from fat: low fat, modified low fat and modified low fat inclusive of 30g of walnuts per day. The walnut group achieved a significantly greater increase in HDL cholesterol-to-total cholesterol ratio and HDL than the other two treatment groups. A 10% reduction in LDL cholesterol was also achieved in the walnut group. There were no significant differences between groups for changes in body weight, percent body fat, total antioxidant capacity, or HbA1c levels.

Wallowitz, M.L., S.S. Comstock, K.H. Roux, S. Sathe, S.S. Teuber, 2004.Walnut allergens. Food Allergy and Intolerance. 5(3)187-95.

This review paper discusses the four English walnut allergens that have been identified—Jug r 1, Jug r 2, Jug r 3 and Jug r 4—along with the recombinant proteins that have been developed for use in the laboratory.Further research may lead to improved diagnostic tests, monitoring of processed foods for cross-contamination and desensitization therapies.

Zambón, D., J. Sabaté, S. Munoz, B. Campero, E. Casals, M. Merlos, J.C. Laguna, E. Ros, 2000.Substituting walnuts for monounsaturated fat improves the serum lipid profile of hypercholesterolemic men and women. A randomized crossover trial. Ann Intern Med. 4:132(7):538-46.

In a 12-week randomized crossover feeding trial, 49 men and women with high cholesterol levels followed a cholesterol-lowering Mediterranean diet, or a walnut diet in which walnuts were substituted for some of the monounsaturated fat in the diet.Researchers found that LDL cholesterol lowered by 5.9% and total cholesterol lowered by 4.1%, out-performing a cholesterol-lowering Mediterranean diet.

Zhao, G., T.D. Etherton, K.R. Martin, S.G. West, P.J. Gillies, P.M. Kris-Etherton, 2004. Dietary α-linolenic acid reduced inflammatory and lipid cardiovascular risk factors in hypercholesterolemic men and women. J. Nutr. 134:2991-97.

This study showed that diets high in polyunsaturated fats (PUFA), especially alpha-linolenic acid (ALA), elicit cardioprotective effects by decreasing lipid and lipoprotein levels and by eliciting vascular anti-inflammatory effects. The fact that ALA has marked, beneficial effects on multiple cardiovascular disease (CVD) risk factors further underscores its potentially important role in CVD risk reduction.

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GENERAL NUTRITION REFERENCES RELEVANT TO TREE NUTS

Alper, C.M., R.D. Mattes, 2002.Effects of chronic peanut consumption on energy balance and hedonics. Int J of Obesity. 26:1129-37.

In this 30-week, cross-over, intervention study, 15 healthy, normal weight adults, aged 33±9 years were placed on three different diets.In one diet, subjects were provided with 505±118 kcal/day as peanuts for 8 weeks with no dietary guidance (free feeding—FF); in another, subjects were given 3 weeks of instructions to add peanuts to their customary diet (addition—ADD); and in the third, peanuts replaced an equal amount of other fats in the diet for 8 weeks (substation—SUB). Subjects were unaware that body weight was a research focus.During FF, peanut consumption resulted in a strong compensatory response (subjects compensated for 66% of the energy provided by the nuts) and body weight gain (1.0 kg) was significantly lower than expected.In the SUB phase both caloric intake and body weight were maintained precisely.Resting energy expenditure was increased by 11% after regular peanut consumption for 19 weeks.Chronic peanut consumption did not lead to a decline in pleasantness or hunger ratings for peanuts, nor did it lead to a hedonic shift for selected snack foods during any of the treatments.Conclusion: Peanuts have a high satiety value and chronic ingestion elicits strong dietary compensation and little change in energy balance.

Ginter, E., 1998.Cardiovascular disease prevention in Eastern Europe. Nutrition. 14(5):452-7.

Over the last three decades the region of highest premature cardiovascular mortality has shifted from the US and Finland to Central and Eastern Europe. Previous studies have shown that the high mortality from CVD in Eastern Europe was not caused by traditional factors alone.Other factors including psychosocial stress and antioxidant deficiencies, alcoholism and smoking are more important than cholesterol or saturated fat intakes in some regions.The intake of antioxidants from domestic and imported vegetables, vegetable oils and nuts in most East European countries has been substantially lower than in the West.More prospective research is needed in the region.

Gregory, J., K. Foster, H. Tyler, M. Wiseman, 1990.The dietary and nutritional survey of British adults. London: HMSO.

Grundy, S.M., N. Abate, M. Chandalia, 2002.Diet composition and the metabolic syndrome: what is the optimal fat intake? Am J Med. 113(9B):25S-29S.

The researchers concluded the studies with the Mediterranean population reveal that in healthier populations, diets relatively high in unsaturated fatty acids are well tolerated and are associated with a low prevalence of both coronary heart disease and type 2 diabetes.

Hodson, L., C.M. Skeaff, W.-A.H., Chisolm, 2001.The effect of replacing dietary saturated fat with polyunsaturated or monounsaturated fat on plasma lipids in free-living young adults. Eur J of Clin Nutr. 55:908-15.

In two randomized cross-over trials, researchers tried to determine the effects of substituting saturated fat rich foods with either n-6 polyunsaturated fat (PUFA) rich foods or monounsaturated fat (MUFA) rich foods on plasma cholesterol, while still adhering to a total fat intake of 30-33% of total calories.In trials I (n=29) and II (n=42), free-living college students eating self-selected diets were asked to follow a diet high in saturated fat for 2½ weeks.During the 2½ week comparison diet, saturated fat foods were replaced with foods rich in n-6 PUFAs (trial I) and in trial II the replacement foods were high in MUFAs.

The results showed that when replacing saturated fats with MUFAs or PUFAs, total fat intakes decreased by 2.9% of calories and 5.1% of calories respectively.Replacing saturated fats with PUFAs decreased total cholesterol by 19%, LDL by 22% and HDL by 14%.Replacing saturated fats with MUFAs decreased total cholesterol by 12%, LDL by 15% and HDL by 4%.The change in the total cholesterol to HDL ratio was similar during trial I and II.The researchers concluded that replacing saturated fats with PUFAs or MUFAs is equally effective in decreasing the total to HDL cholesterol ratio.

Kafatos, A.G., 1999. Diet, antioxidants, and health - case study: the Cretan experience. In: Mediterranean Diets (World Review of Nutrition and Dietetics. Vol. 87).A.P. Simopoulos (ed.) CRC Press LLC.

Kouris-Blazos, A., C. Gnardellis, M.L. Wahlqvist, D. Trichopoulos, W. Lukito, A. Trichopoulous, 1999.Are the advantages of the Mediterranean diet transferable to other populations? A cohort study in Melbourne, Australia. Br J Nutr. 82:57-61.

Krawczyk, T., 2001.Fat in dietary guidelines around the world. Inform. 12:126-40.

Kris-Etherton, P.M., T.A. Pearson, Y. Wan, R.L. Hargrove, K. Moriarty, V. Fishell, T. D. Etherton. 1999. High-monounsaturated fatty acid diets lower both plasma cholesterol and triacylglycerol concentrations. Am J Clin Nutr. 70(6):1009-15.

In this randomized, double-blind, 5-period crossover study with 22 subjects, researchers compared the CVD risk profile of an Average American (AA) diet with those of four cholesterol-lowering diets: American Heart Association Step II diet and three high-monounsaturated fatty acid (MUFA) diets [olive oil (OO), peanuts and peanut butter (PPB) and peanut oil (PO)].The results showed that the MUFA diets lowered total cholesterol by 10% and LDL by 14%--a response comparable to the Step II diet.The OO, PO and PPB diets reduced CVD risk by an estimated 25%, 16% and 21% respectively, whereas the Step II diet lowered CVD risk by only 12%. The high-MUFA diet may be preferable to a low-fat diet in lowering cholesterol because of more favorable effects on the CVD risk profile.

Langseth, L., 1995.Oxidants, antioxidants, and disease prevention.ILSI Europe Concise Monograph Series, Brussels, Belgium: ILSI Europe.

Liu, S., W. Willett, M. Stampfer, et al., 2000.A prospective study of dietary glycemic load, carbohydrate intake and risk of coronary heart disease in US women. Am J Clin Nutr. 71:1455-61.

Researchers prospectively evaluated the relations of the amount and type of carbohydrates with risk of CHD in a cohort of women, aged 38-63 years, from the Nurses’ Health Study.The data suggest that a high dietary glycemic load from refined carbohydrates increases the risk of CHD, independent of known coronary disease risk factors.

Nanos, G.D., D.G. Gerasopoulos, 2001.Fruits, vegetables, legumes and grains.In: The Mediterranean diet: Constituents and health promotion. A.L. Matalas, A. Zampelas, V. Stavrinos, I. Wolinsky (eds) CRC Press, London<.97-125.

N.A.S. 2000. Dietary reference intakes for vitamin C, vitamin E, selenium, and carotenoids. Food and Nutrition Board, Inst. of Med., National Academy Press, Washington, D.C.

N.I.H. Expert Panel on Detection, Evaluation and Treatment of High Cholesterol in Adults, 2001.Executive summary of the third report of the National Cholesterol Education Program expert panel on detection, evaluation & treatment of high blood cholesterol in adults (adult treatment panel III). J Am Med Assn. 285:2486-97.

O’Byrne, D.J., Knauft, D.A., R.B. Shireman, 1997.Low fat-monounsaturated rich diets containing high-oleic peanuts improve serum lipoprotein profiles. Lipids. 32:687-95.

Twelve postmenopausal hypercholesterolemic women, who previously consumed high-fat diets (34% calories from fat), were put on a low fat (26% calories from fat)-monounsaturated rich diet (LFMR: 14% of calories from monounsaturated fat) for 6 months. Thirteen women already eating low fat (LF) diets (24% calories from fat) were also followed to monitor variations in blood lipids.At the end of the study, blood cholesterol decreased 10% and low density lipoprotein decreased 12% in the LFMR group, but did not change in the LF group.Only the LFMR group showed a trend toward beneficial changes in LDL/HDL and apo A-1/apo B ratios.Conclusion: the LFMR diet was well-tolerated and resulted in an improved serum lipid and apolipoprotein profile.[Subjects consumed 35-68 g of high-oleic peanuts/day in the LFMR group.]

Panico, S., I.R. Dello, E. Celentano, R. Galasso, P. Muti, M. Salvatore, M.P. Mancini, 1992.ATENA, a study on the etiology of major chronic diseases in women: design, rationale and objectives. Eur J Epidemiol. 8:601-8.

Pelkman, C.L., V.K. Fishell, D.H. Maddox, T.A. Pearson, D.T. Mauger, P.M. Kris-Etherton, 2004.Effects of moderate-fat (from monounsaturated fat) and low-fat weight-loss diets on serum lipid profile in overweight and obese men and women. Am J Clin Nutr. 79:204-12.

This study evaluated the effects of calorie-controlled, low-fat and moderate-fat diets on changes in lipids and lipoproteins during weight loss and subsequent weight maintenance.In a parallel-arm study design, 53 overweight and obese healthy men and women were assigned to a low-fat diet (18% of calories) or moderate-fat diet (33% of calories and included peanuts and peanut butter) for 6 weeks to achieve weight loss, which was followed by 4 weeks of weight maintenance.All foods were provided and body weight was monitored to ensure equal weight loss between groups.The results showed that the moderate-fat diet produced favorable changes in the lipoprotein profile.Compared with baseline, HDL was unchanged, triacylglycerol and the ratios of total and non-HDL cholesterol to HDL cholesterol were lower at the end of the weight-maintenance period in the moderate-fat diet group.Despite similar weight loss, triacylglycerol rebounded, HDL decreased, and the ratios of total and non-HDL cholesterol to HDL cholesterol did not change during the 10-week interval in the low-fat group.The researchers concluded that a moderate-fat weight-loss and weight-maintenance diet improves the cardiovascular disease risk profile via favorable changes in lipids and lipoproteins.

Rajaram, S., M. Wien, 2001.Vegetarian diets in the prevention of osteoporosis, diabetes, and neurological disorders. In: Sabaté, J., (ed.) Vegetarian Nutrition, CRC Press, Boca Raton<, 109-34.

Rimm, E.B., M.J. Stampfer, 2004.Diet, lifestyle, and longevity—the next steps? JAMA. 292(12):1490-92.

In this editorial, the authors comment that that although the relation of lifestyle and health outcomes will continue to be refined, there is enough evidence now to take action.  The US spends billions of dollars on chronic disease treatments and intervention for risk factors, and if we spent only a fraction of that on promoting healthful lifestyles and primary prevention we’d probably be much healthier.

Serra Majem, L., N. Armas, B.L. Ribas, 2000.Food consumption and food sources of energy and nutrients in Canary Islands (1997-1998) [in Spanish]. Arch Latinoam Nutr. 50(suppl 1): 23-33.

Serra-Majem L, R. García-Closas, L. Ribas, C. Pérez-Rodrigo, J. Aranceta, 2001. Food patterns of Spanish schoolchildren and adolescents: The enKid Study. Public Health Nutrition. 4(6A): 1433-8.

Slimani, N., P. Ferrari, M. Ocke, et al., 2000.Standardization of the 24-hour diet recall calibration method used in the European prospective investigation into cancer and nutrition (EPIC): general concepts and preliminary results. Eur J Clin Nutr. 54(12):900-17.

Trichopoulou, A., T. Costacou, C. Bamia, D. Trichopoulou, 2003.Adherence to a Mediterranean diet and survival in a Greek population. NEJM. 348:2599-2608.

In this population-based, prospective investigation involving 22,043 adults in Greece, researchers studied the effects of a Mediterranean diet on mortality. Greater adherence to the traditional Mediterranean diet was associated with a significant reduction in total mortality.According to the authors, “After adjusting for age, sex, education, smoking status, BMI, waist-to-hip ratio, energy expenditure score and total energy intake, the only individual measures that were predictive of total mortality were the intake of fruits and nuts and the ratio of monounsaturated fats to saturated fats.”

Trichopoulou, A., E. Vasilopoulou, 2000.Mediterranean diet and longevity. Br J Nutr. 84(suppl 2):S205-9.

Trichopoulou, A., P. Lagiou, 1997.Healthy traditional Mediterranean diet: an expression of culture, history, and lifestyle. Nutrition Reviews. 55(11):383-9.

USDA Dietary Guidelines for Americans 2000, 5th Edition, Center for Nutrition Policy and Promotion.

Willett, W.C., 2003.Eat, drink, and be healthy.The Harvard Medical School Guide to Healthy Eating.Simon & Schuster Source, NY.

According to the author, contrary to popular opinion, nuts aren’t junk food.They’re actually a great source of protein and other nutritional goodies.An ounce of almonds, walnuts, peanuts, or pistachios provides about 8 grams of protein, the same as a glass of milk.While nuts have quite a bit of fat, it is mostly unsaturated fats that reduce LDL cholesterol and keep HDL cholesterol high.

However it happens, the message is the same—nuts are good for you, if eaten the right way.Eat nuts instead of chips or chocolate as a snack.They’ll take the edge off hunger every bit as well as true junk food, they taste as good as or better than junk food, and they provide healthy nutrients to boot.

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