Ingesting phytochemicals, unlike ingesting vitamins and certain minerals, is not considered essential for maintaining human lives. But scientific findings tentatively suggest that habitual ample intakes of such compounds may contribute to disease prevention. More than 2,500 varieties of soy are being cultivated. But soy oil, soy sauce, and some other soy products lack them. The most abundant isoflavone in soy is genistein, which has been the focus of most isoflavone research.
Soybeans are the only significant dietary source of genistein and daidzein.
The BBI may have utility in preventing and suppressing carcinogenesis. About 34 million Americans have excessive cholesterol in their blood. That elevated plasma cholesterol is a major risk factor for CHD has been established. A decrease in plasma cholesterol of 1 percent decreases the risk of CHD by 2 percent. The inhabitants of the Far East and Southeast Asia typically derive about 10 percent of their daily protein intakes from soybeans, whereas in the U.S. soybeans contribute minimally to such intake.