Abstract

Soybean is a leguminous plant native to eastern Asia (Liu et al. 2008). Soybean is cultivated worldwide, with the U.S. being responsible for more than 50% of the world's production of this important food. Soybean grains are rich in protein content (see aminoacids composition, Table 1); therefore constitute a useful source of food. It is consumed as cooked beans, soy sauce, soy milk and tofu (soybean curd). Also, a vegetable oil is obtained from soybeans, rich in polyunsaturated fatty acids. This legume is also a good source of several phytochemicals such as isoflavones and lignans, molecules with antioxidant properties that, among other effects, might help to fight and prevent several pathologies. For these reasons, these compounds have been intensively studied at basic and at the clinical level. Soybean consumption benefits, especially in the cardiovascular system, have been related to its important protein content, high levels of essential fatty acids, vitamins and minerals. Nevertheless, there has been controversy as to the extent to which soybean is a health- promoting food. We address some aspects of these issues in this chapter.