An ounce of nuts a day keeps the doctor away.
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An ounce of nuts a day keeps the doctor away.

Eating nuts can decrease rates of heart disease and cancer and even extend life expectancy, according to a new study in the 'New England Journal of Medicine' conducted at Harvard University. Researchers followed 119,000 medical professionals for 30 years and found that people who ate a handful of nuts every day had 29 percent less deadly heart disease and were 20 percent less likely to die of any cause. "We're not exactly sure why this is happening, but we think nuts help reduce inflammation and impact metabolic pathways in a way that lowers the risk of obesity, type 2 diabetes, and certain cancers, which ultimately lessens the chances of an early death," says senior author Dr. Charles Fuchs.

In the study, researchers took into account body mass index, smoking, and other disease risk factors, and found that nuts showed these benefits for all groups. "Whether they were obese or lean or on a high-fat or a low-fat diet, nuts' effect was constant," says Fuchs. The study didn't look at specific nut types, but, he says, the best advice is to eat an ounce of nuts daily and aim for a wide variety. "About 24 almonds, 18 cashews, or 35 peanuts a day should do the trick," says Fuchs.