Dietary changes that may be helpful: Soybeans contain compounds called phytoestrogens that are related in structure to estrogen, though some reports show soy’s estrogenic activity to be quite weak. Soy is known to affect the menstrual cycle in premenopausal women. Societies with high consumption of soy products have a low incidence of hot flashes during menopause. In one double-blind trial, supplementation with 60 grams of soy protein caused a 33% decrease in the number of hot flashes after four weeks and a 45% reduction after 12 weeks. However, in further analysis of the data in this trial, researchers credit constituents in soybeans other than phytoestrogens for the therapeutic effect. In one controlled clinical trial, high intake of phytoestrogens from soy and flaxseed reduced both hot flashes and vaginal dryness; however, much (though not all) of the benefit was also seen in the control group. As a result of these studies, doctors often recommend that women experiencing menopausal symptoms eat tofu, soy milk, tempeh, roasted soy nuts, and other soy-based sources of phytoestrogens. Soy sauce contains very little phytoestrogen content, and many processed foods made from soybean concentrates have insignificant levels of phytoestrogens. Supplements containing isoflavones extracted from soy are commercially available, and flaxseed (as opposed to flaxseed oil) is also a good source of phytoestrogens.