In the study, researchers examined data from the Netherlands Cohort Study, which includes information about 120,000 Dutch 55- to 69-year-old men and women from 1986 to the present day. They measured nut intake by asking about portion size and the frequency at which the participants ate tree nuts, peanuts, and peanut butter.
“It was remarkable that substantially lower mortality was already observed at consumption levels of 15 grams of nuts or peanuts on average per day (half a handful),” Professor Piet van den Brandt, the project leader and epidemiologist, said in the press release. “A higher intake was not associated with further reduction in mortality risk. This was also supported by a meta-analysis of previously published studies together with the Netherlands Cohort Study, in which cancer and respiratory mortality showed this same dose-response pattern.”
It turns out that eating pure peanuts instead of peanut butter is better: The researchers found no improvement among people who ate peanut butter, which typically contains non-healthy additives like salt and vegetable oils. But in those who ate peanuts, their mortality risk was lowered.
It’s been known for some time that nuts — which are rich in essential nutrients like fiber, protein, minerals, monounsaturated and polyunsaturated fatty acids, and antioxidants — have plenty of health benefits. One 2010 study notes that “by virtue of their unique composition, nuts are likely to beneficially impact health outcomes. Epidemiologic studies have associated nut consumption with a reduced incidence of coronary heart disease and gallstones in both genders and diabetes in women,” and “studies consistently show that nut intake has a cholesterol-lowering effect.”
But the new study is really the first to show that those benefits are so wide-ranging and encompassing — and can extend past heart health and helping people manage weight/diabetes.