Studies on functional foods in Japan--state of the art.

This paper pinpoints the "tertiary" function of foods which, different from the conventional "primary" and "secondary" functions that are related to nutrition and preference, respectively, is understood to be directly involved in the modulation of our physiological systems such as the immune, endocrine, nerve, circulatory, and digestive systems. Insights into this newly defined function are particularly important in that the intake of some physiologically functional constituents of foods could be effective in preventing diseases that may be caused by disorders in these physiological systems. Technologically, it has become feasible to design and produce physiologically functional foods (simply, functional foods) that are expected to satisfy in whole or in part a today's demand for disease prevention by eating. Such public expectations are reflected in the activation and development of systematic, large-scale studies on foods as seen in "Grant-in-Aid" research sponsored by the Ministry of Education, Science, and Culture. Meanwhile, the Ministry of Health and Welfare has initiated a policy of officially approving functional foods in terms of "foods for specified health uses" as defined by new legislation. Up to now (October 1995), 58 items have thus been approved. The first was a hypoallergenic rice product approved as of June 1, 1993. Here I discuss details of studies on rice-based functional foods. Other basic and applied studies directed toward the tertiary function, with future perspectives for functional foods, are also discussed.