Genistein Source Naturals
Genistein, an isoflavone phytonutrient derived from soybeans, has been the focus of scientific research since 1966. Studies have shown that genistein can bind to the same receptor sites as estrogen. Soybeans are the only significant dietary source of genistein; however, the amount of soy foods necessary to meet the body's needs can be difficult to incorporate into today's diet. In Asia, where soy is a staple, the daily intake can be up to 20 times that of a Western diet. Source Naturals Genistein is made from isoflavone-rich soybean powder that yields a consistent standardized isoflavone content. This unique chemical-free process requires approximately 400 pounds of soybeans to yield just one pound of finished product.

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Genistein Supplement Facts:
Isoflavone-Rich - 2 g
Soybean Powder (Soylife) Yielding:
   Daidzein - 34 mg
   Glycitein - 20 mg
   Genistein - 8 mg
   Total Isoflavones - 62 mg

Genistein isoflavone benefit
Genistein is one of the best known and studied isoflavones. Isoflavones are types of flavonoids found in plants. Compounds from plants that have estrogen-like properties are called phytoestrogens.

Genistein and blood pressure
Chronic soy milk consumption has modest, but significant hypotensive action in those with hypertension. This hypotensive action was correlated with the urinary excretion of the isoflavone genistein.

Genistein and hot flashes
Genistein and other flavonoids do not appear to have a significant effect in reducing the severity of hot flashes, at least not as much as estrogen. However, one small study indicates flaxseed could be helpful.

Genistein and heart disease
Daily supplements of genistein, a naturally occurring compound found in soy, combined with calcium, and vitamin D, as well as a healthy diet, may help prevent heart disease and help regulate blood sugar in postmenopausal women with bone loss. Dr. Francesco Squadrito, from the University of Messina, Italy tested the effects genistein on cardiovascular disease risk factors in nearly 400 healthy women, average age of about 54 years, who went through menopause at about age 49. The women followed identical, fat-restricted diets and avoided eating any soy products for 4-weeks prior to beginning the supplements. Study participants were not using hormone replacement therapy commonly prescribed to prevent bone loss in postmenopausal women. Half the women took daily supplements of 54 mg of purified genistein and the other half to take identically appearing placebo supplements. All the supplements contained 500 mg calcium carbonate and 400 IU vitamin D per tablet. The women continued the healthy diet throughout the 2-year study duration. After 12 and 24 months of study participation, Dr. Francesco Squadrito and colleagues found the combination of genistein, calcium, vitamin D, and a healthy diet had positive therapeutic effects on some predictors for heart disease. Their findings also suggest that genistein may have a positive effect on the metabolism of blood sugar and, therefore, may help prevent the development of diabetes. By contrast, the researchers found no difference in cholesterol levels between the women taking genistein supplements or placebo. These findings suggest that genistein supplements may help prevent the development of coronary artery disease in postmenopausal women with bone loss. The Journal of Clinical Endocrinology and Metabolism, August 2007.

Genistein and osteoporosis studies
The effects of phytoestrogen isoflavones on bone density in women: a double-blind, randomized, placebo-controlled trial.
Atkinson C, Compston JE, Day NE, Dowsett M, Bingham SA. MRC Biostatistics Unit, Institute of Public Health, Robinson Way, Cambridge, United Kingdom. Am J Clin Nutr. 2004 Feb;79(2):326-33.
Isoflavone phytoestrogen therapy has been proposed as a natural alternative to hormone replacement therapy (HRT). HRT has a beneficial effect on bone, but few trials in humans have investigated the effects of isoflavones on bone. The objective of the study was to determine the effect on bone density of a red clover-derived isoflavone supplement that provided a daily dose of 26 mg biochanin A, 16 mg formononetin, 1 mg genistein, and 0.5 mg daidzein for 1 y. Effects on biochemical markers of bone turnover and body composition were also studied. Women aged 49-65 y (n = 205) were enrolled in a double-blind, randomized, placebo-controlled trial; 177 completed the trial. Bone density, body composition, bone turnover markers, and diet were measured at baseline and after 12 mo. Loss of lumbar spine bone mineral content and bone mineral density was significantly lower in the women taking the isoflavone supplement than in those taking the placebo. There were no significant treatment effects on hip bone mineral content or bone mineral density, markers of bone resorption, or body composition, but bone formation markers were significantly increased (P = 0.04 and P = 0.01 for bone-specific alkaline phosphatase and N-propeptide of collagen type I, respectively) in the intervention group compared with placebo in postmenopausal women. Interactions between treatment group and menopausal status with respect to changes in other outcomes were not significant. These data suggest that, through attenuation of bone loss, isoflavones have a potentially protective effect on the lumbar spine in women.

Genistein questions
Q. What is the right dosage of genistein for long term use?
   A. Not enough human research has been done to determine the idea genisitein dosage. Much depends on a person's diet.

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