According to a study by researchers from the Harvard T.H. Chan School of Public Health, higher walnut consumption – both in terms of the amount and frequency – may be associated with a lower risk of death and an increase in life expectancy among older adults in the U.S., compared to those who do not consume walnuts.
"What we've learned from this study is that even a few handfuls of walnuts per week may help promote longevity, especially among those whose diet quality isn't great to begin with. It's a practical tip that can be feasible for a number of people who are looking to improve their health, which is top of mind for many people," said Yanping Li, Senior Research Scientist at the Department of Nutrition at Harvard T.H. Chan School of Public Health, and lead investigator of this research.
This study, supported by the California Walnut Commission and published in Nutrients, found five or more servings of walnuts per week (one serving = one ounce) may provide the greatest benefit for mortality risk and life expectancy. Eating five or more servings per week was associated with a 14% lower risk of death (from any cause), 25% lower risk of dying from cardiovascular diseases, and a gain in about 1.3 years of life expectancy, compared to those who didn't consume walnuts.
Consuming walnuts two to four times per week could have its benefits, too, with the study finding a 13% lower risk of death overall, 14% lower risk of dying from cardiovascular diseases, and a gain in about one year of life, compared to non-walnut consumers.
Interestingly, even among people with a suboptimal diet, as measured by a validated index based on foods and nutrients predictive of chronic disease risk, just a one-half serving per day increase in walnut consumption was associated with benefits, including 12% reduced risk of death and 26% lower risk of death from cardiovascular diseases, specifically.