Legumes by which we mean all kinds of beans, chickpeas, split peas, and lentils, are an excellent source of many essential nutrients…vitamins, minerals, fibers, antioxidants. And, not just an excellent source; perhaps the single cheapest source. In terms of nutrition density per penny, the four that really pull away from the pack are pinto beans, lentils, black beans, and kidney beans.
And, all that nutritional quality may have beneficial effects on excess body weight, insulin resistance, high cholesterol, inflammation, and oxidative stress—all “major cardiovascular risk factors.” So, do men and women who eat more beans tend to have less heart disease? Yes, suggesting that “increasing legume intake may be an important part of a dietary approach to the primary prevention of coronary heart disease in the general population”—meaning prevention of heart disease in the first place. But, maybe those eating more bean burritos are just eating fewer beef burritos? They took that into account, controlling for meat intake, fruits and vegetables, and smoking, and exercise. And, still, the bean-eaters appeared to be protected.
Note the highest category was eating legumes four or more times a week. In my Daily Dozen, I recommend people eat legumes three times—a day! In Costa Rica, they were able to find enough people eating beans every day. And, even after controlling for many of the same things, like intake of saturated fat and cholesterol, one bean serving a day was “associated with a 38% reduction in the risk of [heart attack].” Yeah, but do you actually get to live longer, too? Yes, apparently so: an 8% lower all-cause mortality, again after adjusting for other dietary factors. You can’t control for everything, though. You can’t really prove cause-and-effect until you… put it to the test.