Prevention of osteoporosis by foods and dietary supplements. Soybean isoflavone and bone metabolism

Abstract

Soybean isoflavones show structural similarity to estradiol and therefore are known as phytoestrogen. Recently, isoflavones have received a great deal of attention for their preventive roles against hormone dependent diseases including postmenopausal osteoporosis, hyperlipidemia and cancer. Particularly, a number of studies have reported that soybean isoflavones inhibited bone loss in both female and male osteoporotic animal models as well as in postmenopausal women. On the other hand, since a kind of tablet with concentrated isoflavones has been recently applied for foods for specified health use (FOSHU), which are functional foods permitted to label a health claim by the Ministry of Health, Labor and Welfare in Japan, Food Safety Commission submitted a report the upper limit of daily isoflavone aglycon intake from FOSHU as well as from soybean products. This report demonstrates the effects of isoflavones on bone metabolism and safety.