In a new study of data from the long-term Nurses Health Study (women) and the Health Professionals Follow-up Study (men), Dr. Ying Bao and colleagues from Harvard Medical School and affiliates found a strong association between consumption of various types of nuts and a decreased risk of death. Their results were published in the current New England Journal of Medicine.
The researchers recorded the diets of over 76,000 women and 42,000 men by administering food frequency questionnaires every 2 to 4 years from 1980 on. Data from individuals who reported having cancer, stroke, heart disease or angina were excluded from the study. Various lifestyle characteristics such as activity levels as well as body weight and BMI were also assessed. Then, the correlation between frequency of nut consumption and mortality from any cause was calculated.
Compared with participants who ate nuts less often, those who consumed nuts more frequently had healthier lifestyles. They were leaner, less likely to smoke, more likely to exercise and use multivitamins. Also, they ate more fruits and vegetables and consumed more alcohol.
Statistical analyses revealed a significant trend towards a decreased risk of death from any cause with increased nut consumption. This was true for both peanuts and for tree nuts (peanuts are actually legumes, while tree nuts are not). For example, compared to those who reported never eating nuts, those who ate them once per week had an 11 percent lower risk of death, and those who ate them five or more times per week had a 17 percent lower risk. These trends were similar for both men and women, as well as for specific causes such as cancer, cardiovascular disease, and heart disease. Interestingly, they found that contrary to what one might expect, increased nut consumption was not linked to increased weight gain, which they said was also true in other studies.
The authors noted that their although these results were consistent with findings of other, smaller studies, Given the observational nature of our study, it is not possible to conclude that the observed inverse association between nut consumption and mortality reflects cause and effect.
ACSH s Dr. Ruth Kava added In my opinion the most important take-home message from this study is that a healthy lifestyle can certainly include nut consumption. It is highly unlikely, however, that a couch potato can reduce his or her risk of death by eating nuts while watching TV.