“A handful of nuts a day keeps the doctor away” lacks the poetic metre of the daily-apple version, but it might contain at least as much medical validity, according to research published in the New England Journal of Medicine.
In looking at diet and disease of 118,000 people over a 30-year period, researchers found that frequent nut consumption was associated with a lower risk of all-cause and disease-specific death. Compared to people who did not eat nuts, those who ate a 28-gram serving of nuts seven or more times a week had a 20% lower risk of all-cause death. Eating nuts five or more times per week was also associated with an 11% lower risk of cancer-related death, a 24% lower risk of death from respiratory disease, a 25% lower risk of cardiovascular-related death and a 29% lower risk of heart disease.
There are about 20 to 25 almonds in a 28-gram serving, and 15 to 20 peanuts or cashews in a 28-gram serving. In the study, peanuts and tree nuts (almonds, pecans, walnuts, pine nuts, etc.) had similar effects on lowering mortality.
In general, regular nut eaters were different from those in the study who didn’t frequently eat nuts. The nut eaters were leaner, less likely to smoke, more likely to exercise, take multivitamin supplements, eat more fruits and vegetables and drink alcohol.
As the researchers point out, this was an observational study, in which people’s self-reported habits were compared to their incidence of disease and death. As such, cause and effect – does eating nuts lead to lowered disease risk, or do people who are healthier tend to like nuts? – can’t be established.
Nonetheless, the researchers wrote, there’s “a wealth of existing observational and clinical trial data to support health benefits of nut consumption on many chronic diseases.” On the basis of earlier studies, in 2003 the US Food and Drug Administration concluded that eating 42 grams per day of most nuts “may reduce the risk of heart disease.”