Dietary guidelines now recommend eating more plant-based foods, rather than animal-derived foods. Most of these recommendations include nuts because of their unique nutritional profile. Nuts are seeds; they are high in unsaturated fatty acids, vitamins, minerals, dietary fiber and unique bioactive compounds, which may explain why they are so good for us.

Eating nuts will reduce your risk of cardiovascular disease (CVD) and coronary heart disease (CHD), according to a large study that looked at the connection between the consumption of specific kinds of nuts and major cardiovascular events. The researchers reviewed participants' tree nut and peanut consumption because, although peanuts are legumes, their fatty acid and nutrient profile is similar to that of nuts that grow on trees, like walnuts and almonds. Nut consumption was measured using food questionnaires, which were updated every four years.

“Raw nuts, if possible unpeeled and otherwise unprocessed, may be considered natural health capsules that can easily be incorporated into any heart-protective diet… ”

More than 210,000 people in three long-term health studies were followed for up to 32 years. None of the participants had heart problems at the start of the study. The primary endpoint was a major cardiovascular event, such as myocardial infarction or heart attack, stroke or a fatal cardiovascular event. The team also checked for fatal and non-fatal strokes.

There was a consistent association between increased total nut consumption and a decreased risk of CVD and CHD — the more nuts a person consumed, the lower his or her risk of a cardiac event, particularly a fatal one.

Walnuts were particularly beneficial. Study participants who ate walnuts at least once a week had a 19 percent lower risk of CVD and a 21 percent lower risk of CHD than those who never ate walnuts. Those who reported eating peanuts or tree nuts two or more times per week has a 13 percent and 15 percent lower risk of CVD, respectively, than those who said they did not eat peanuts or tree nuts. People who ate peanuts and tree nuts also had a 15 percent lower and 23 percent lower risk, respectively, of CHD than those who did not. Peanut butter did not appear to have any protective effect.

Regular nut consumption could reduce the risk of chronic diseases in the general population, Marta Guasch-Ferre, lead author of the study and a research fellow at Harvard's T.H. Chan School of Public Health, told TheDoctor, adding, “Our findings support recommendations to increase the intake of a variety of nuts as part of a healthy diet.”

Future research will hopefully provide more clues as to the nutritional punch packed by different kinds of nuts, but in the meantime, a handful of nuts a day will fill you up and help your heart. As Emilio Ros, director of the Lipid Clinic and Senior Consultant, Endocrinology and Nutrition Service, Hospital Clínic, Barcelona, Spain, wrote in a related editorial, “Raw nuts, if possible unpeeled and otherwise unprocessed, may be considered natural health capsules that can easily be incorporated into any heart-protective diet to further cardiovascular well-being and promote healthy aging.”

The study and related editorial are published in the Journal of the American College of Cardiology.