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Nut consumption is associated with decreased health risk factors for cardiovascular disease and metabolic syndrome in U.S. adults: NHANES 1999–2004.

Wed, 21 Dec 2011 08:30:00 -0600

O’Neil, C.E., D.R. Keast, T.A. Nicklas, V.L. Fulgoni, 2011. Nut consumption is associated with decreased health risk factors for cardiovascular disease and metabolic syndrome in U.S. adults: NHANES 1999–2004. Journal of the American College of Nutrition. 30(6):502–510.

Background: Few recent epidemiologic studies have assessed the effect that nut consumption (including tree nuts and peanuts) has on health risks, including metabolic syndrome (MetS). Objective: This study compared the health risk for cardiovascular disease, type 2 diabetes, and MetS of nut consumers with that of nonconsumers. Design: Adults 19+ years (n = 13,292) participating in the 1999–2004 National Health and Nutrition Examination Survey were used. Intake from 24-hour recalls was used to determine intake. Nut/tree nut consumers consumed ≥¼ ounce per day. Covariate-adjusted means, standard errors, and prevalence rates were determined for the nut consumption groups. Results: The prevalence of nut consumers was 18.6% ± 0.7% and 21.0% ± 0.9% in those 19–50 years and 51 years and older, respectively. Nut consumption was associated with a decreased body mass index (27.7 kg/m² ± 0.2 vs 28.1 ± 0.1 kg/m², p<0.05), waist circumference (95.6 ± 0.4 cm vs 96.4 ± 0.3 cm, p < 0.05), and systolic blood pressure (121.9 ± 0.4 mmHg vs 123.20 ± 0.3 mmHg, p < 0.01) compared with nonconsumers. Tree nut consumers also had a lower weight (78.8 ± 0.7 kg vs 80.7 ± 0.3 kg, p < 0.05). Nut consumers had a lower percentage of two risk factors for MetS: hypertension (31.5% ± 1.0% vs 34.2% ± 0.8%, p < 0.05) and low high density lipoprotein-cholesterol (HDL-C) (29.6% ± 1.0% vs 34.8% ± 0.8%, p < 0.01). Tree nut consumers had a lower prevalence of four risk factors for MetS: abdominal obesity (43.6% ± 1.6% vs 49.5% ± 0.8%, p < 0.05), hypertension (31.4% ± 1.2% vs 33.9% ± 0.8%, p < 0.05), low HDL-C (27.9% ± 1.7% vs 34.5% ± 0.8%, p < 0.01), high fasting glucose (11.4% ± 1.4% vs 15.0% ± 0.7%, p < 0.05), and a lower prevalence of MetS (21.2% ± 2.1% vs 26.6% ± 0.7%, p < 0.05). Conclusion: Nut/tree nut consumption was associated with a decreased prevalence of selected risk factors for cardiovascular disease, type 2 diabetes, and MetS.

Nuts improve diet quality compared to other energy-dense snacks while maintaining body weight.

Tue, 11 Oct 2011 15:56:22 -0500

Tey, S.L., R. Brown, A. Gray, A. Chisholm, C. Delahunty, 2011. Nuts improve diet quality compared to other energy-dense snacks while maintaining body weight. Journal of Nutrition and Metabolism. doi:10.1155/2011/357350.

Previous studies have reported that regular nut consumption reduces cardiovascular disease (CVD) risk and does not promote weight gain despite the fact that nuts are energy-dense. However, no studies have investigated the body composition of those regularly consuming nuts compared to similar intakes of other snacks of equal energy density. This parallel study (n = 118) examined the effects of providing daily portions (~1100 kJ/d) of hazelnuts, chocolate, or potato crisps compared to a control group receiving no snacks for twelve weeks. Effects on body weight and composition, blood lipids and lipoproteins, resting metabolic rate (RMR), appetite indices, and dietary quality were compared. At week 12, there was no significant difference in any of the outcome measurements between the groups except for dietary quality, which improved significantly in the nut group. Nuts can be incorporated into the diet without adversely affecting body weight and can improve diet quality.

Red meat consumption and risk of type 2 diabetes: 3 cohorts of US adults and an updated meta-analysis.

Tue, 11 Oct 2011 15:37:12 -0500

Pan, A., Q. Sun, A.M. Bernstein, J.E. Manson, W.C. Willett, F.B. Hu, 2011. Red meat consumption and risk of type 2 diabetes: 3 cohorts of US adults and an updated meta-analysis. Am J Clin Nutr. doi: 10.3945/ajcn.111.018978.

Background: The relation between consumption of different types of red meats and risk of type 2 diabetes (T2D) remains uncertain. Objective: We evaluated the association between unprocessed and processed red meat consumption and incident T2D in US adults. Design: We followed 37,083 men in the Health Professionals Follow-Up Study (1986–2006), 79,570 women in the Nurses’ Health Study I (1980–2008), and 87,504 women in the Nurses’ Health Study II (1991–2005). Diet was assessed by validated food-frequency questionnaires, and data were updated every 4 y. Incident T2D was confirmed by a validated supplementary questionnaire. Results: During 4,033,322 person-years of follow-up, we documented 13,759 incident T2D cases. After adjustment for age, BMI, and other lifestyle and dietary risk factors, both unprocessed and processed red meat intakes were positively associated with T2D risk in each cohort (all P-trend <0.001). The pooled HRs (95% CIs) for a one serving/d increase in unprocessed, processed, and total red meat consumption were 1.12 (1.08, 1.16), 1.32 (1.25, 1.40), and 1.14 (1.10, 1.18), respectively. The results were confirmed by a meta-analysis (442,101 participants and 28,228 diabetes cases): the RRs (95% CIs) were 1.19 (1.04, 1.37) and 1.51 (1.25, 1.83) for 100 g unprocessed red meat/d and for 50 g processed red meat/d, respectively. We estimated that substitutions of one serving of nuts, low-fat dairy, and whole grains per day for one serving of red meat per day were associated with a 16–35% lower risk of T2D.

Effects of walnut consumption on cognitive performance in young adults.

Tue, 11 Oct 2011 15:15:54 -0500

Pribis P., R.N. Bailey, A.A. Russell, M.A. Kilsby, M. Hernandez, W.J. Craig, T. Grajales, D.J. Shavlik, J. Sabatè, 2011. Effects of walnut consumption on cognitive performance in young adults. Br J Nutr. doi:10.1017/S0007114511004302

Walnuts contain a number of potentially neuroprotective compounds like vitamin E, folate, melatonin, several antioxidative polyphenols and significant amounts of n-3 α-linolenic fatty acid. The present study sought to determine the effect of walnuts on verbal and non-verbal reasoning, memory and mood. A total of sixty-four college students were randomly assigned to two treatment sequences in a crossover fashion: walnuts-placebo or placebo-walnuts. Baseline data were collected for non-verbal reasoning, verbal reasoning, memory and mood states. Data were collected again after 8 weeks of intervention. After 6 weeks of washout, the intervention groups followed the diets in reverse order. Data were collected once more at the end of the 8-week intervention period. No significant increases were detected for mood, non-verbal reasoning or memory on the walnut-supplemented diet. However, inferential verbal reasoning increased significantly by 11.2 %, indicating a medium effect size (P = 0.009; d = 0.567). In young, healthy, normal adults, walnuts do not appear to improve memory, mood or non-verbal reasoning abilities. However, walnuts may have the ability to increase inferential reasoning.

Polymeric proanthocyanidins from Sicilian pistachio (Pistacia vera L.) nut extract inhibit lipopolysaccharide-induced inflammatory response in RAW 264.7 cells.

Tue, 06 Sep 2011 23:07:21 -0500

Gentile, C., M. Allegra, F. Angileri, A.M. Pintaudi, M.A. Livrea, L. Tesoriere, 2011. Polymeric proanthocyanidins from Sicilian pistachio (Pistacia vera L.) nut extract inhibit lipopolysaccharide-induced inflammatory response in RAW 264.7 cells. Eur J Nutr. doi: 10.1007/s00394-011-0220-5.

Background: Positive effects of pistachio nut consumption on plasma inflammatory biomarkers have been described; however, little is known about molecular events associated with these effects. Purpose: We studied the anti-inflammatory activity of a hydrophilic extract from Sicilian Pistacia L. (HPE) in a macrophage model and investigated bioactive components relevant to the observed effects. Methods: HPE oligomer/polymer proanthocyanidin fractions were isolated by adsorbance chromatography, and components quantified as anthocyanidins after acidic hydrolysis. Isoflavones were measured by gradient elution HPLC analysis. RAW 264.7 murine macrophages were pre-incubated with either HPE (1- to 20-mg fresh nut equivalents) or its isolated components for 1 h, then washed before stimulating with lipopolysaccharide (LPS) for 24 h. Cell viability and parameters associated with Nuclear Factor-κB (NF-κB) activation were assayed according to established methods including ELISA, Western blot, or cytofluorimetric analysis. Results: HPE suppressed nitric oxide (NO) and tumor necrosis factor-α (TNF-α) production and inducible NO-synthase levels dose dependently, whereas inhibited prostaglandin E2 (PGE₂) release and decreased cyclooxygenase-2 content, the lower the HPE amount the higher the effect. Cytotoxic effects were not observed. HPE also caused a dose-dependent decrease in intracellular reactive oxygen species and interfered with the NF-κB activation. Polymeric proanthocyanidins, but not isoflavones, at a concentration comparable with their content in HPE, inhibited NO, PGE₂, and TNF-α formation, as well as activation of IκB-α. Oligomeric proanthocyanidins showed only minor effects. Conclusions: Our results provide molecular evidence of anti-inflammatory activity of pistachio nut and indicate polymeric proanthocyanidins as the bioactive components. The mechanism may involve the redox-sensitive transcription factor NF-κB. Potential effects associated with pistachio nut consumption are discussed in terms of the proanthocyanidin bioavailability.

In-shell pistachio nuts reduce caloric intake compared to shelled nuts.

Fri, 02 Sep 2011 16:09:46 -0500

Honselman, C.S., J.E. Painter, K.J. Kennedy-Hagan, A. Halvorson, K. Rhodes, T.L. Brooks, K. Skwir, 2011. In-shell pistachio nuts reduce caloric intake compared to shelled nuts. Appetite. 57:414-417.

It was hypothesized that consuming in-shell pistachios, compared to shelled pistachios, causes individuals to consume less. A convenience sample of students at a mid-western university (n = 140) was recruited, asking them to evaluate a variety of brands of pistachios. A survey at the end of class determined fullness and satisfaction. Subjects entering the classroom were given a 16-ounce cup and asked to self-select a portion of pistachios. Portion weight was recorded and subjects consumed pistachios at their leisure during class. At class end, pistachios remaining in the cup were weighed and total consumption by weight was determined. The caloric content of each portion was then calculated. In condition one, subjects offered in-shell pistachios consumed an average of 125 calories. In condition two, subjects offered shelled pistachios consumed an average of 211 calories; a difference of 86 calories. Subjects in condition one consumed 41% fewer calories compared to subjects in condition two (p ≤ .01). Fullness and satisfaction ratings were not significantly different (p ≥ .01). Caloric intake was influenced by the initial form of the food. The difference in calories consumed may be due to the additional time needed to shell the nuts or the extra volume perceived when consuming in-shell nuts.

Measured energy value of pistachios in the human diet.

Fri, 02 Sep 2011 15:57:32 -0500

Baer, D.J., S.K. Gebauer, J.A. Novotny, 2011. Measured energy value of pistachios in the human diet. British Journal of Nutrition. doi:10.1017/S0007114511002649.

Previous studies have suggested that lipid from nuts is more poorly absorbed than that from other food sources. If lipid from nuts is poorly absorbed, then the metabolisable energy contained in the nuts is less than that predicted by the Atwater general factors. A crossover feeding study was conducted in which sixteen volunteers consumed pistachios for 3 weeks as part of a controlled diet. Pistachio doses were 0, 42 and 84 g/d. Urine and fecal samples were collected, and urine, feces and diet were analyzed for N, fat, total dietary fiber, ash and combustible energy. Blood was also collected after each treatment period and analyzed for plasma lipids. Energy value of pistachio nuts was calculated from differences in energy excretion during the different dietary treatments. The measured energy density of pistachios was found to be 22·6 kJ/g, which is 5% less than the currently accepted energy value of 23·7 kJ/g, as calculated using the Atwater general factors. The pistachio nut intervention lowered LDL-cholesterol by 6%, but did not significantly change plasma total cholesterol, HDL-cholesterol or TAG. In conclusion, pistachio nuts contain less metabolisable energy than that calculated from the Atwater general factors. Accurate information about metabolisable energy content of foods is important for reliable food labeling.

Differential effects of walnuts vs almonds on improving metabolic and endocrine parameters in PCOS.

Fri, 02 Sep 2011 15:48:14 -0500

Kalgaonkar, S., R.U. Almario, D. Gurusinghe, E.M. Garamendi, W. Buchan, K. Kim, S.E. Karakas, 2011. Differential effects of walnuts vs almonds on improving metabolic and endocrine parameters in PCOS. European Journal of Clinical Nutrition. 65:386–393.

Background/Objectives: Polycystic ovary syndrome (PCOS) is commonly associated with insulin resistance, dyslipidemia and increased inflammation, which all benefit from dietary intake of monounsaturated and n-3 polyunsaturated fatty acids (MUFA and n-3 PUFA). Our goal was to compare the effects of MUFA-rich almonds vs n-3/n-6 PUFA-rich walnuts on metabolic and endocrine parameters in PCOS. Subjects/Methods: Thirty-one PCOS patients randomly received either walnuts or almonds containing 31 g of total fat per day for 6 weeks. At the beginning and at the end, anthropometric parameters, fasting lipids, phospholipid-fatty acids, inflammatory markers, androgens, oral glucose tolerance tests (OGTT) and frequently sampled intravenous-GTT were obtained. Results: Weight remained stable. Within group, walnuts increased the n-3/n-6 essential PUFA in the diet and plasma phospholipids. Walnuts decreased low-density lipoprotein-cholesterol by 6% from 3.76±0.27 to 3.38±0.22 mmol/l (P=0.05) and apoprotein B by 11% from 0.72±0.04 to 0.64±0.05 g/l (P<0.03). Although almonds also reduced low-density lipoprotein-cholesterol by 10% and apoprotein B by 9%, these were not significant. Walnuts increased insulin response during OGTT by 26% (P<0.02). Both walnuts and almonds increased adiponectin (walnuts from 9.5±1.6 to 11.3±1.8 mg per 100 ml, P=0.0241; almonds from 10.1±1.5 to 12.2±1.4 mg/dl, P=0.0262). Walnuts decreased HgBA1 from 5.7±0.1 to 5.5±0.1% (P=0.0006) with significant intergroup difference from almonds (P=0.0470). Walnuts increased sex hormone-binding globulin from 38.3±4.1 to 43.1±4.3 nmol/l (P=0.0038) and almonds reduced free androgen index from 2.6±0.4 to 1.8±0.3 (P=0.0470). Conclusion: Nut intake exerted beneficial effects on plasma lipids and androgens in PCOS.

Crossover study of diets enriched with virgin olive oil, walnuts or almonds. Effects on lipids and other cardiovascular risk markers.

Fri, 02 Sep 2011 15:21:32 -0500

Damasceno, N.R.T., A. Pe´rez-Heras, M. Serra, M. Cofa´n, A. Sala-Vila, J. Salas-Salvado´, E. Ros, 2011. Crossover study of diets enriched with virgin olive oil, walnuts or almonds. Effects on lipids and other cardiovascular risk markers. Nutr Metab Cardiovasc Dis. 21 (Suppl 1):S14-20.

Background and aims: Virgin olive oil (VOO) and nuts are basic components of the Mediterranean diet, a heart-healthy dietary pattern. Nuts have well known cholesterol lowering effects, while evidence is unclear for VOO. We designed a study in hypercholesterolemic patients to assess the effects on serum lipids and other intermediate markers of cardiovascular risk of replacing 40% of the fat in the background diet with VOO, walnuts or almonds. Methods and Results: After a 4 week run-in period with a healthy diet, eligible candidates were randomized into three diet sequences in a crossover design, with a common background diet enriched with VOO, walnuts or almonds, lasting 4 weeks each. Outcomes were changes of serum lipids and oxidation and inflammation markers, measured by standard methods. Plasma fatty acids were determined by gas chromatography to assess compliance. In 18 participants completing the study (9 women, mean age 56 y, BMI 25.7 kg/m2), LDL cholesterol was reduced from baseline by 7.3%, 10.8% and 13.4% after the VOO, walnut and almond diets, respectively (P Z 0.001, Friedman test). Total cholesterol and LDL/HDL ratios decreased in parallel. LDL-cholesterol decreases were greater than predicted from dietary fatty acid and cholesterol exchanges among diets. No changes of other lipid fractions, oxidation analytes or inflammatory biomarkers were observed. Plasma fatty acid changes after each diet sequence supported good compliance.

Dietary walnuts inhibit colorectal cancer growth in mice by suppressing angiogenesis.

Sat, 02 Jul 2011 13:52:42 -0500

Nagel, J.M., M. Brinkoetter, F. Magkos, X. Liu, J.P. Chamberland, S. Shah, J. Zhou, G. Blackburn, C.S. Mantzoros, 2011. Dietary walnuts inhibit colorectal cancer growth in mice by suppressing angiogenesis. Nutrition. Jul 26. [Epub ahead of print]

OBJECTIVE: Animal studies have demonstrated that dietary supplementation with flaxseed oil inhibits colorectal cancer growth. Recent data indicate that walnuts have strong antiproliferative properties against colon cancer cells in vitro but no previous study has assessed the effects of walnuts in vivo or performed a joint evaluation of flaxseed oil and walnuts. The aim of the present study was to examine the effect of dietary walnuts on colorectal cancer in vivo and to comparatively evaluate their efficacy in relation to flaxseed oil. METHODS: HT-29 human colon cancer cells were injected in 6-wk-old female nude mice. After a 1-wk acclimation period, mice (n = 48) were randomized to diets containing ∼19% of total energy from walnuts, flaxseed oil, or corn oil (control) and were subsequently studied for 25 d. RESULTS: Tumor growth rate was significantly slower in walnut-fed and flaxseed-fed mice compared with corn oil-fed animals (P < 0.05) by 27% and 43%, respectively. Accordingly, final tumor weight was reduced by 33% and 44%, respectively (P < 0.05 versus control); the differences between walnut and flaxseed diets did not reach significance. We found no differences among groups in metabolic and hormonal profile, serum antioxidant capacity, or inflammation (P > 0.05). However, walnuts and flaxseed oil significantly reduced serum expression levels of angiogenesis factors, including vascular endothelial growth factor (by 30% and 80%, respectively), and approximately doubled total necrotic areas despite smaller tumor sizes (P < 0.05 versus control). Dietary walnuts significantly decreased angiogenesis (CD34 staining; P = 0.017 versus control), whereas this effect did not reach significance in the flaxseed oil group (P = 0.454 versus control). CONCLUSION: We conclude that walnuts in the diet inhibit colorectal cancer growth by suppressing angiogenesis. Further studies are needed to confirm our findings in humans and explore underlying mechanisms.

Dietary walnut suppressed mammary gland tumorigenesis in the C(3)1 TAg mouse.

Sat, 02 Jul 2011 13:49:19 -0500

Hardman, W.E., G. Ion, J.A. Akinsete,T.R. Witte, 2011. Dietary walnut suppressed mammary gland tumorigenesis in the C(3)1 TAg mouse. Nutr Cancer. Jul 20. [Epub ahead of print]

Walnuts contain multiple ingredients that, individually, have been shown to slow cancer growth, including omega-3 fatty acids, antioxidants, and phytosterols. In previous research, consumption of walnuts has slowed the growth of implanted breast cancers. We wanted to determine whether regular walnut consumption might reduce the risk for developing cancer. Homozygous male C(3)1 TAg mice were bred with female SV129 mice consuming either the control AIN-76 diet or the walnut-containing diet. At weaning, the female hemizygous pups were randomized to control or walnut-containing diets and followed for tumor development. Compared to a diet without walnuts, consumption of walnuts significantly reduced tumor incidence (fraction of mice with at least one tumor), multiplicity (number of glands with tumor/mouse), and size. Gene expression analyses indicated that consumption of the walnut diet altered expression of multiple genes associated with proliferation and differentiation of mammary epithelial cells. A comparison with another dietary intervention indicated that the omega 3 content alone did not account for the extent of tumor suppression due to the walnut. The results of this study indicate that walnut consumption could contribute to a healthy diet to reduce risk for breast cancer.

Nuts as a replacement for carbohydrates in the diabetic diet.

Wed, 29 Jun 2011 09:35:10 -0500

Jenkins, D.J.A., C.W.C. Kendall, M.S. Banach, K. Srichaikul, E. Vidgen, S. Mitchell, T. Parker, S. Nishi, B. Bashyam, R. de Souza, C. Ireland, R.G. Josse, 2011. Nuts as a replacement for carbohydrates in the diabetic diet. Diabetes Care. 34:1-6. doi: 10.2337/dc11-0338

OBJECTIVE: Fat intake, especially monounsaturated fatty acid (MUFA), has been liberalized in diabetic diets to preserve HDL cholesterol and improve glycemic control, yet the exact sources have not been clearly defined. Therefore, we assessed the effect of mixed nut consumption as a source of vegetable fat on serum lipids and HbA_1c in type 2 diabetes. RESEARCH DESIGN AND METHODS: A total of 117 type 2 diabetic subjects were randomized to one of three treatments for 3 months. Supplements were provided at 475 kcal per 2,000-kcal diet as mixed nuts (75 g/day), muffins, or half portions of both. The primary outcome was change in HbA_1c. RESULTS: The relative increase in MUFAs was 8.7% energy on the full-nut dose compared with muffins. Using an intention-to-treat analysis (n = 117), full-nut dose (mean intake 73 g/day) reduced HbA_1c (−0.21% absolute HbA_1c units, 95% CI −0.30 to −0.11, P < 0.001) with no change after half-nut dose or muffin. Full-nut dose was significantly different from half-nut dose (P = 0.004) and muffin (P = 0.001), but no difference was seen between half-nut dose and muffins. LDL cholesterol also decreased significantly after full-nut dose compared with muffin. The LDL cholesterol reduction after half-nut dose was intermediate and not significantly different from the other treatments. Apolipoprotein (apo) B and the apoB:apoA1 ratio behaved similarly. Nut intake related negatively to changes in HbA_1c (r = −0.20, P = 0.033) and LDL cholesterol (r = −0.24, P = 0.011). CONCLUSIONS: Two ounces of nuts daily as a replacement for carbohydrate foods improved both glycemic control and serum lipids in type 2 diabetes.

The impact of pistachio intake alone or in combination with high-carbohydrate foods on post-prandial glycemia.

Tue, 28 Jun 2011 23:15:50 -0500

Kendall, C.W., A.R. Josse, A. Esfahani, D.J. Jenkins, 2011. The impact of pistachio intake alone or in combination with high-carbohydrate foods on post-prandial glycemia. Eur J Clin Nutr. 65(6):696-702.

Background/Objectives: Dietary strategies that reduce post-prandial glycemia are important in the prevention and treatment of diabetes and coronary heart disease (CHD). This may be achieved by addition of high-quality protein and fat contained in pistachio nuts, to carbohydrate-containing foods or meals. Subjects/Methods: A total of 10 healthy volunteers (3 males, 7 females); aged 48.3±6.4 years; Body mass index (BMI) 28.0±4.8 kg/m(2) participated in two studies. Study 1 assessed the dose-response effect of 28, 56 and 84 g pistachios consumed alone or co-ingested with white bread (50 g available carbohydrate); Study 2 assessed the effective dose (56 g) of pistachios on post-prandial glycemia consumed with different commonly consumed carbohydrate foods (50 g available carbohydrate). Relative glycemic responses (RGRs) of study meals compared with white bread, were assessed over the 2 h post-prandial period. Results:The RGRs of pistachios consumed alone expressed as a percentage of white bread (100%) were: 28 g (5.7±1.8%); 56 g (3.8±1.8%); 84 g (9.3±3.2%), P<0.001. Adding pistachios to white bread resulted in a dose-dependent reduction in the RGR of the composite meal; 28 g (89.1±6.0, P=0.100); 56 g (67.3±9.8, P=0.009); 84 g (51.5±7.5, P<0.001). Addition of 56 g pistachios to carbohydrate foods significantly reduced the RGR: parboiled rice (72.5±6.0) versus rice and pistachios (58.7±5.1) (P=0.031); pasta (94.8±11.4) versus pasta and pistachios (56.4±5.0) (P=0.025); whereas for mashed potatoes (109.0±6.6) versus potatoes and pistachios, (87.4±8.0) (P=0.063) the results approached significance. Conclusions: Pistachios consumed alone had a minimal effect on post-prandial glycemia and when taken with a carbohydrate meal attenuated the RGR. The beneficial effects of pistachios on post-prandial glycemia could, therefore, be part of the mechanism by which nuts reduce the risk of diabetes and CHD.

The effect of pistachio shells as a visual cue in reducing caloric consumption.

Tue, 28 Jun 2011 23:07:37 -0500

Kennedy-Hagan K., J.E. Painter, C. Honselman, A. Halvorson, K. Rhodes, K. Skwir, 2011. The effect of pistachio shells as a visual cue in reducing caloric consumption. Appetite. doi:10.106/j.appet. 2011.06.003

It was hypothesized that pistachio shells left in sight as visual cues of consumption will cause individuals to consume less. A convenience sample of faculty and staff at a mid-western university (n=118) were recruited as subjects for the study. The subjects were told they were going to evaluate a variety of brands of pistachios and were surveyed at the end of each day to determine their fullness and satisfaction. The subjects were offered pistachios on their desks for an 8-h period on two separate days and were able to consume the pistachios at their leisure during that time. Subjects began each day with a sixteen ounce bowl filled with four ounces of pistachios in the shell. They were also provided with a second sixteen ounce bowl, in which they were instructed to place the empty shells from the pistachios they consumed. Every 2h throughout the day pistachios were added in two ounce increments. In condition one, the shells remained in the bowls until the end of the day, whereas in condition two, the shell bowls were emptied every 2h throughout the day. In condition one, subjects consumed an average of 216 calories. In condition two, subjects consumed an average of 264 calories, a difference of 48 calories. Subjects in condition one consumed significantly (p≤.05) fewer calories, yet fullness and satisfaction ratings were not significantly (p≥.05) different between conditions. Leaving pistachio shells as a visual cue to consumption may help consumers consume fewer calories. Learning outcomes: Individuals will be aware of the impact of visual cues of dietary intake on total food consumption.

Changes in diet and lifestyle and long-term weight gain in women and men.

Thu, 23 Jun 2011 21:51:39 -0500

Mozaffarian, D., T. Hao, E.B. Rimm, W.C. Willett, F.B. Hu, 2011. Changes in diet and lifestyle and long-term weight gain in women and men. N Engl J Med 2011; 364:2392-2404.

Background: Specific dietary and other lifestyle behaviors may affect the success of the straightforward-sounding strategy “eat less and exercise more” for preventing long-term weight gain. Methods: We performed prospective investigations involving three separate cohorts that included 120,877 U.S. women and men who were free of chronic diseases and not obese at baseline, with follow-up periods from 1986 to 2006, 1991 to 2003, and 1986 to 2006. The relationships between changes in lifestyle factors and weight change were evaluated at 4-year intervals, with multivariable adjustments made for age, baseline body-mass index for each period, and all lifestyle factors simultaneously. Cohort-specific and sex-specific results were similar and were pooled with the use of an inverse-variance–weighted meta-analysis. Results: Within each 4-year period, participants gained an average of 3.35 lb (5th to 95th percentile, −4.1 to 12.4). On the basis of increased daily servings of individual dietary components, 4-year weight change was most strongly associated with the intake of potato chips (1.69 lb), potatoes (1.28 lb), sugar-sweetened beverages (1.00 lb), unprocessed red meats (0.95 lb), and processed meats (0.93 lb) and was inversely associated with the intake of vegetables (−0.22 lb), whole grains (−0.37 lb), fruits (−0.49 lb), nuts (−0.57 lb), and yogurt (−0.82 lb) (P≤0.005 for each comparison). Aggregate dietary changes were associated with substantial differences in weight change (3.93 lb across quintiles of dietary change). Other lifestyle factors were also independently associated with weight change (P<0.001), including physical activity (−1.76 lb across quintiles); alcohol use (0.41 lb per drink per day), smoking (new quitters, 5.17 lb; former smokers, 0.14 lb), sleep (more weight gain with <6 or >8 hours of sleep), and television watching (0.31 lb per hour per day). Conclusions: Specific dietary and lifestyle factors are independently associated with long-term weight gain, with a substantial aggregate effect and implications for strategies to prevent obesity.

Protective effects of walnut extract against amyloid beta peptide-Induced cell death and oxidative stress in PC12 cells.

Thu, 02 Jun 2011 13:46:59 -0500

Muthaiyah B., M.M. Essa, V. Chauhan, A. Chauhan, 2011. Protective effects of walnut extract against amyloid beta peptide-Induced cell death and oxidative stress in PC12 cells. Neurochem Res. Jun 25. [Epub ahead of print]

Amyloid beta-protein (Aβ) is the major component of senile plaques and cerebrovascular amyloid deposits in individuals with Alzheimer's disease. Aβ is known to increase free radical production in neuronal cells, leading to oxidative stress and cell death. Recently, considerable attention has been focused on dietary antioxidants that are able to scavenge reactive oxygen species (ROS), thereby offering protection against oxidative stress. Walnuts are rich in components that have anti-oxidant and anti-inflammatory properties. The inhibition of in vitro fibrillization of synthetic Aβ, and solubilization of preformed fibrillar Aβ by walnut extract was previously reported. The present study was designed to investigate whether walnut extract can protect against Aβ-induced oxidative damage and cytotoxicity. The effect of walnut extract on Aβ-induced cellular damage, ROS generation and apoptosis in PC12 pheochromocytoma cells was studied. Walnut extract reduced Aβ-mediated cell death assessed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) reduction, and release of lactate dehydrogenase (membrane damage), DNA damage (apoptosis) and generation of ROS in a concentration-dependent manner. These results suggest that walnut extract can counteract Aβ-induced oxidative stress and associated cell death.

Alpha-linolenic acid increases cholesterol efflux in macrophage-derived foam cells by decreasing stearoyl CoA desaturase 1 expression: evidence for a farnesoid-X-receptor mechanism of action.

Thu, 02 Jun 2011 13:43:30 -0500

Zhang J., P.M. Kris-Etherton, J.T. Thompson, D.B. Hannon, P.J. Gillies, J.P. Vanden Heuvel, 2011. Alpha-linolenic acid increases cholesterol efflux in macrophage-derived foam cells by decreasing stearoyl CoA desaturase 1 expression: evidence for a farnesoid-X-receptor mechanism of action. J Nutr Biochem. Jun 7. [Epub ahead of print]

Increased cholesterol efflux from macrophage-derived foam cells (MDFCs) is an important protective mechanism to decrease lipid load in the atherosclerotic plaque. Dietary alpha-linolenic acid (ALA), an omega-3 polyunsaturated fatty acid (PUFA), decreases circulating cholesterol, but its role in cholesterol efflux has not been extensively studied. Stearoyl CoA desaturase 1 (SCD1) is the rate-limiting enzyme in the synthesis of monounsaturated fatty acids (MUFAs). Endogenous MUFAs are preferentially incorporated into triglycerides, phospholipids and cholesteryl ester, which are abundant in atherosclerotic plaque. This study investigated the mechanisms by which ALA regulated SCD1 and subsequent effect on cholesterol storage and transport in MDFCs. Small interfering RNA (siRNA) also was applied to modify SCD1 expression in foam cells. Alpha-linolenic acid treatment and SCD1 siRNA significantly decreased SCD1 expression in MDFCs. The reduction of SCD1 was accompanied with increased cholesterol efflux and decreased intracellular cholesterol storage within these cells. Alpha-linolenic acid activated the nuclear receptor farnesoid-X-receptor, which in turn increased its target gene small heterodimer partner (SHP) expression, and decreased liver-X-receptor dependent sterol regulatory element binding protein 1c transcription, ultimately resulting in repressed SCD1 expression. In conclusion, repression of SCD1 by ALA favorably increased cholesterol efflux and decreased cholesterol accumulation in foam cells. This may be one mechanism by which dietary omega-3 PUFAs promote atherosclerosis regression.

Carotid and femoral plaque burden is inversely associated with the alpha-linolenic acid proportion of serum phospholipids in Spanish subjects with primary dyslipidemia.

Wed, 11 May 2011 13:00:33 -0500

Vila A.S., Cofan, I. Nunez, R. Gilabert, M. Junyent, E. Ros, 2011. Carotid and femoral plaque burden is inversely associated with the alpha-linolenic acid proportion of serum phospholipids in Spanish subjects with primary dyslipidemia. Atherosclerosis. 214(1):209-14.

OBJECTIVE: α-Linolenic acid (ALA), the vegetable n-3 fatty acid, appears to have antiatherosclerotic properties akin to those of marine n-3 fatty acids. A prior study in a US population with low fish intake showed an inverse association between ALA intake and carotid plaque. We examined the association between the ALA status and advanced carotid and femoral atherosclerosis in subjects at high cardiovascular disease risk from Spain, a country with low coronary heart disease (CHD) rates and high fish consumption. METHODS: Cross-sectional study of 211 patients with primary dyslipidemia, with determination of fatty acid composition of serum phosphatidylcholine by gas chromatography and plaque outcomes (frequency, number, maximum height and sum of plaque heights) in 19 carotid and femoral arteries by sonography. RESULTS: In multivariate regression analyses after adjusting for age, gender, lipid genotype, BMI, smoking, hypertension, diabetes mellitus, APOE4 genotype, prior statin treatment, and serum proportions of other unsaturated fatty acids known to relate to atherosclerosis, the proportion of ALA showed an inverse association with the risk of carotid plaque (OR [95% CI] 0.66 [0.44-0.91]) and concomitant carotid and femoral artery plaque (0.57 [0.38-0.86]). CONCLUSION: The inverse relationship between ALA in serum phosphatidylcholine and plaque burden in carotid and femoral arteries supports its antiatherosclerotic effect independently of fish-derived n-3 fatty acids. However, whether ALA enrichment in phospholipids is beneficial per se or is a surrogate of the consumption of bioactive compounds in parent foods deserves further research.

The glycemic effect of nut-enriched meals in healthy and diabetic subjects.

Tue, 10 May 2011 22:33:44 -0500

Kendall C.W., A. Esfahani, A.R. Josse, L.S. Augustin, E. Vidgen, D.J. Jenkins, 2011. The glycemic effect of nut-enriched meals in healthy and diabetic subjects. Nutr. Metab. Cardiovasc. Dis. 21(Suppl 1):S34-9.

BACKGROUND AND AIMS: The intake of nuts has been linked to a reduced risk of cardiovascular disease (CVD) and diabetes in large cohort studies. One potential contributing mechanism may be the ability of nuts to improve post-meal glycemic response. We, therefore, examined the effect of nuts alone and in combination with white bread on postprandial glycemia. METHODS AND RESULTS: 30, 60 and 90 g (approximately 1, 2 and 3 ounces) of mixed nuts were consumed with and without 50 g available carbohydrate from white bread by 10-14 normoglycemic and 5-10 type 2 diabetic subjects. Glycemic response (GR) was assessed by calculating the incremental area under the 2 h blood glucose curve. All three doses of mixed nuts, when fed alone, significantly reduced the glycemic response in both normoglycemic and diabetic patients. Furthermore, in the normoglycemic subjects, adding nuts to white bread progressively reduced the GR of the meal by 11.2 ± 11.6%, 29.7 ± 12.2% and 53.5 ± 8.5% for the 30, 60, and 90 g doses (P = 0.354, P = 0.031 and P < 0.001, respectively), while in subjects with type 2 diabetes, the effect was half of that seen in the non-diabetic subjects (P = 0.474, P = 0.113 and P = 0.015, respectively). CONCLUSION: Nuts alone have little effect on post-meal blood glucose response. Furthermore, when taken with bread, nuts progressively reduce the glycemic response in a dose-dependent manner. While these findings support a short-term benefit for nuts in postprandial glucose response, more studies are required to determine whether these acute benefits result in long-term improvements in glycemic control.

Nuts, hypertension and endothelial function.

Mon, 28 Mar 2011 23:54:53 -0500

Casas-Agustench, P., P. López-Uriarte, E. Ros, M. Bulló, J. Salas-Salvadó, 2011. Nuts, hypertension and endothelial function. Nutr Metab Cardiovasc Dis. 2011 21(Suppl 1):S21-33.

BACKGROUND AND AIMS: High blood pressure (BP) is considered a major risk factor for cardiovascular disease. Among lifestyle factors, diet plays a key role in the prevention and control of high BP. Therefore, it is important to elucidate which dietary components can exert beneficial effects on BP through modulation of endothelial function (EF) or by other mechanisms. In this paper we review the role of nutrients, foods, particularly nuts, and dietary patterns on BP control. DATA SYNTHESIS: Because nuts are low in sodium and contain significant amounts of mono- and polyunsaturated fatty acids, fiber, minerals such as magnesium, potassium and calcium, and antioxidants, they have been suggested as potentially protective foods against hypertension. Limited evidence from prospective studies and clinical trials suggests that nut consumption has a beneficial effect on both BP and EF. However, BP changes were a secondary outcome in nut feeding trials and no study used ambulatory BP monitoring as the standard for BP measurements. CONCLUSIONS: Further clinical trials, ideally using ambulatory BP monitoring, are needed to establish the potential protective effect of nut consumption on hypertension and vascular reactivity.