Eating walnuts prevents premature death and extends life expectancy.

Walnuts are a nutrient-dense food, rich in omega-3 fatty acids, protein, fiber, and many vitamins and minerals. Evidence suggests that consuming walnuts as part of a healthy diet improves cognitive function and cardiovascular health and reduces the risk of developing certain types of cancer. Findings from a 2021 study suggest that eating walnuts reduces the risk of dying from all causes of premature death and promotes longevity.

The investigation involved more than 93,000 healthy men and women (average age, 63 years) who were enrolled in the Nurses' Health Study and the Health Professionals Follow-up Study, two ongoing studies focused on identifying risk factors that drive chronic disease. Every two to four years, participants completed a food frequency questionnaire in which they answered questions about their walnut consumption as well as other dietary habits. The investigators ranked the participants according to the number of servings of walnuts they consumed each week. They also assessed the overall quality of the participants' diets, based on foods and nutrients that predict chronic disease risk. They tracked the participants' disease and death rates for approximately 20 years.

They found that during the 20-year period, nearly half of the participants died. Compared to participants who never ate walnuts, the risk of death from all causes among those who ate fewer than one serving of walnuts per week was 5 percent lower; for one serving, 6 percent lower; for two to four servings, 13 percent lower; and for those who ate five or more servings, 14 percent lower. When the investigators looked at individual causes of death, they found that participants who ate walnuts more than five times a week were 25 percent less likely to die from cardiovascular disease than those who ate no walnuts. The benefits associated with eating walnuts was independent of the participants' overall diet quality; however, among participants whose diet was suboptimal, eating one-half serving of walnuts daily decreased their risk of premature death by 12 percent. Eating walnuts five times a week or more also prolonged life expectancy, with women gaining 2.43 years, and men gaining 1.56 years.

These findings suggest that eating walnuts reduces the risk of dying from all causes of premature death and promotes longevity, especially among people whose diets may be lacking in other beneficial components. Some of the benefits of walnuts may be attributed to their high alpha-linolenic acid content. Alpha-linolenic acid is a type of omega-3 fatty acid that exerts potent cardioprotective and neuroprotective properties. Learn more about the health benefits of omega-3s in this episode featuring Dr. Bill Harris.

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