Soybeans are an excellent source of phytosterols. Isoflavones in soy may inhibit the growth of breast, endometrial, prostate, and colon cancers. Phytosterols may reduce colon cancer risk. High levels of estrogen have been related to escalated risks for breast cancer and other hormone-related cancers. By mimicking and interfering with estrogen, isoflavone may prevent estrogen from binding to cell receptors and thereby inhibit the cancer process.
Soy protein contains less sulfuric amino acids and phosphorus than animal proteins.
Large amounts of sulfur and phosphorus can cause the body to lose calcium, one of the most important minerals in retaining health bones. Isoflavone in soy may inhibit bone loss and stimulate bone formation. This may reduce the risk for osteoporosis, the bone-thinning process so common in postmenopausal women. Isoflavone in soy foods may relieve symptoms of menopause including vaginal dryness and the inability to regulate body temperature, which often leads to sweats and hot flashes. Hot flashes occur in a significant number of pre- and perimenopausal women.