Tree Nut Consumption and Risk of Colorectal Cancer in Women: Most Comprehensive Study to Date on Nut Consumption and Colorectal Cancer in Women in the European Journal of Clinical Nutrition

Davis, CA, May 7, 2015 – In a large prospective study published online in the European Journal of Clinical Nutrition, researchers looked at the association between nut consumption and risk of colorectal cancer among 75,680 women in the Nurses’ Health Study, with no previous history of cancer.  

Women who consumed a one-ounce serving of nuts, including tree nuts (such as almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts),  two or more times per week had a 13% lower risk of colorectal cancer  (RR, 0.87; 95% CI, 0.72-1.05; P=0.06) compared to those who rarely consumed nuts. “While this association was not statistically significant,” stated lead researcher, Ying Bao, MD, ScD, from the Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, “a possible inverse association was suggested and this has been observed in previous prospective studies as well.” 

The current study is the most comprehensive study to date looking at long-term nut consumption and colorectal cancer risk and the one with the longest follow-up of 30 years. Colorectal cancer is the second most common cancer in women and the third most common cancer in men worldwide. Risk of colorectal cancer is higher among individuals with excess body weight, and type 2 diabetes. Interestingly, women in this study who consumed the most nuts tended to be leaner.  According to Dr. Bao, “Since nuts have been associated with less weight gain and a decreased risk of type 2 diabetes, increasing nut consumption may result in reduced risk of developing colorectal cancer.”

Previous research has shown that women in this same cohort, who consumed a one-ounce serving of nuts two or more times per week, had a significantly reduced risk of pancreatic cancer (RR, 0.65; 95% CI, 0.47-0.92; P=0.007) compared to those who largely abstained from nuts. “These findings are very encouraging,” stated Maureen Ternus, M.S., R.D., Executive Director of the International Tree Nut Council Nutrition Research & Education Foundation (INC NREF). “While we’ve known for years that 1.5 ounces  (or 1/3 cup) of nuts per day can help reduce the risk of heart disease, more and more research is showing the potential beneficial effect of nut consumption on other chronic diseases such as diabetes and cancer.”