Effects of dietary traditional fermented soybean on reproductive hormones, lipids, and glucose among postmenopausal women in northern Thailand.

Isoflavone in soybean and its products have numerous beneficial health effects. A number of clinical studies have demonstrated that dietary soy isoflavone can relieve menopausal symptoms, lower risks of breast cancer, and lower cholesterol and glucose. Among the various effects of isoflavone, the role of cholesterol and glucose reduction seems to be well documented; however, other effects such as reproductive hormones were inconclusive and inconsistent. The main objective of the present study was to investigate the effects of six-month dietary traditional fermented soybean intake on BMI, reproductive hormones, lipids, and glucose among postmenopausal women. Subjects were women with their last menstrual period occurring at least 12 months prior to selection by interview and health screening from Baan Tham Village, Phayao Province, Thailand. A total of 60 women were divided into 2 groups: experimental group (n=31) and reference group (n=29). The experimental group was permitted to continue their usual diet, and supplemented with fermented soybean for 6 months. The fermented soybean provided approximately 60 mg of isoflavone per day. The remarkable findings were that dietary fermented soybean had favorable effects on progesterone and cholesterol, but had no effects on estradiol, glucose, and triglycerides. Although estradiol and glucose in the experimental group did not change, a decrease of estradiol and an increase of glucose were found in the reference group. Our results, therefore, suggest that fermented soybean may have beneficial effects on reproductive hormones and cholesterol, and they would be warrant further detail investigations.