By Harold McGee
Beans and peas are generally excellent sources of a number of nutrients, including protein, iron, various B vitamins, folic acid, and starch or oil. Varieties with colored seed coats provide valuable antioxidants. Among all the legumes, however, soybeans appear to have unusual potential for affecting human health. Epidemiological studies have shown that countries in which soybeans are a staple food, notably China and Japan, have significantly lower rates of heart disease and cancer. It may be that soybeans are part of the explanation.