Genistein and Daidzen, Isoflavones, 1000 mg
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:
Isoflavones - 2 grams
Soybean Powder (Soylife) Yielding:
   Daidzein - 34 mg
   Glycitein - 20 mg
   Genistein - 8 mg
   Total Isoflavones - 62 mg

Suggested Use: one genistein tablet with breakfast, or as recommended by your health care professional.

Genistein benefit
In spite of an extensive literature on the effects of dietary genistein, questions still exist as to its potential overall benefits as a component of the human diet. Genistein is synthesized in plants from the flavanone naringenin by a novel ring migration reaction catalyzed by the cytochrome P450 enzyme isoflavone synthase (IFS). IFS genes have recently been cloned from a number of plant species, and production of genistein can be now achieved in non-legumes by recombinant DNA approaches.

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 other flavonoids do not appear to have a significant effect in reducing the severity of hot flashes, at least not as much as estrogen.

Genistein and osteoporosis
Effects of the phytoestrogen genistein on bone metabolism in osteopenic postmenopausal women: a randomized trial.
Ann Intern Med. 2007 Jun 19;146(12):839-47. Azienda Ospedaliera Universitaria Policlinico G. Martino, University of Messina, Messina, Italy.
Observational studies and small trials of short duration suggest that the isoflavone genistein reduces bone loss, but the evidence is not definitive. 389 postmenopausal women with a bone mineral density (BMD) less than 0.795 g/cm2 at the femoral neck and no significant comorbid conditions took 54 mg of genistein daily for 24 months. Both the genistein and placebo tablets contained calcium and vitamin D. Twenty-four months of treatment with genistein has positive effects on bone mineral density in osteopenic postmenopausal women.

Prostate cancer
Genistein and resveratrol, alone and in combination, suppress prostate cancer in SV-40 tag rats.
Prostate. 2009 Aug 7. Harper CE, Cook LM, Patel BB, Wang J, Eltoum IA, Arabshahi A, Shirai T, Lamartiniere CA. Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, Alabama.
Chemoprevention utilizing dietary agents is an effective means to slow the development of prostate cancer. We evaluated the potential additive and synergistic effects of genistein and resveratrol for suppressing prostate cancer in the Simian Virus-40 T-antigen (SV-40 Tag) targeted probasin promoter rat model, a transgenic model of spontaneously developing prostate cancer. Rats were fed genistein or resveratrol (250 mg/kg AIN-76A diet) alone and in combination, and a low-dose combination (83 mg genistein + 83 mg resveratrol/kg diet). Genistein and resveratrol, alone and in combination, suppress prostate cancer development in the SV-40 Tag model. Regulation of SRC-3 and growth factor signaling proteins are consistent with these nutritional polyphenols reducing cell proliferation and increasing apoptosis in the prostate.

Hormone replacement therapy and menopause
Recent studies indicate that long term replacement with Premarin (horse derived estrogens) and synthetic progesterone increases the risk for heart disease, cancer, blood clots and gallbladder disease. 
   The field of hormone or herbal therapy during or after menopause is very complicated and there is no consensus within the medical community regarding the best option for long term therapy. The medical community seems to be shifting its viewpoint on hormone replacement. It appears that most traditional doctors now prefer using low doses of hormones for a brief period of time to treat menopausal symptoms, but prefer not to continue hormone replacement therapy indefinitely as in the past. Therefore, it may be a reasonable approach to use low dose estrogens for a brief period during the most severe times of hot flashes, then use herbs and supplements for long term post-menopausal therapy. Some herbs to consider include Black-Cohosh and the herb Chaste-Berry.

Genistein and fat tissue effect
Genistein affects adipose tissue deposition in a dose-dependent and gender-specific manner.
Endocrinology. 2006 Dec;147(12):5740-51. 3rd Laboratory/Biotechnology, and Department of Diagnostics, Civic Hospital of Brescia, 25123 and Department of Pathology, University of Brescia, Italy.
The soy isoflavone genistein targets adipose tissue and elicits physiological effects that may vary based on dietary intake. We hypothesized that the adipose effects of genistein are dose and gender dependent. Four-week-old C57BL/6 male and female mice received daily oral doses of genistein (50-200,000 microg/kg.d) or 17beta-estradiol (E2) (5 microg/kg.d) for 15 d or a diet containing 800 ppm genistein. Genistein increased epididymal and renal fat pad and adipocyte size at doses up to 50,000 microg/kg.d or at 800 ppm in the diet in males but not in females. The alteration in adipocity correlated with changes in peripheral insulin resistance. In conclusion, nutritional doses of genistein are adipogenic in a gender-specific manner, whereas pharmacological doses inhibited adipose deposition.

Genistein Research Update
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 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 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. I'm taking two tablets of Genistein, one of 5HTP and one of Mind Power a day. Besides the uses of these herbals I also wanted to decrease my libido, but it doesn't work very well. Do you recomend any other supplement or dosis?
   A. 5-htp is known to decrease libido but Mind Power may increase it. We are not sure about genistein. Good Night Rx may be an option that you could discuss with your doctor. It is not taken more than 3 nights a week.

Q. My girlfriend was diagnosed 18 month ago with a Stage IV poorly differentiated cancer from apparent ovarian origin. She has undergone 11 chemos (carboplatine and gemcitabine)) and then enjoyed a 8-10 month complete remission. There is now a recurrence and she's back with the same protocol. To enhance the chemo and reduce side effects I think that Genistein could be of interest, but I'd like to know more about possible interaction with the chemo and risks coping with a disease that may be hormone dependant.
   A. Not enough human research is available to determine if genistein could be helpful in this condition.

Q. My 69 year old mother is diagnosed with Leiomyosarcoma. Her large tumor (>10cm) was resected from her lower abdomen {pelvis region}. After much research, I have grown to admire the anti-cancer therapy benefits of genistein supplementation. I attempt to be careful before including any supplement in her "diet"... I find no specific mention that genistein is appropriate, or is not appropriate, for Leiomyosarcoma patients. Will your Staff please comment? Additional Information: Mom had a hysterectomy in 1979 after dealing with painful (uterine and extra-uterine) endometriosis for nearly 25 years. Following hysterectomy, Mom took estrogen replacement drug for 15-20 years. Comment: There have been reported cases of women with [benign] endometriosis developing "transformed" cancer in the peritoneal cavity many years after cessation of endometriosis symptoms and/or hysterectomy... albeit, only very rare cases of Leiomyosarcoma. There probably exists only a very low probability that this cancer may have originated from uterine tissue 30+/- years ago(?).
   A. We could only find one laboratory study regarding genistein and leiomyosarcoma and we really don't know what would happen if genistein supplements are taken orally in terms of their effect on this condition.

Genistein inhibition of fast Na+ current in uterine leiomyosarcoma cells is independent of tyrosine kinase inhibition.
Biochim Biophys Acta. 1996 Jan. Kusaka M, Sperelakis N. Department of Molecular and Cellular Physiology, College of Medicine, University of Cincinnati, OH 45267, USA.
Possible regulation of fast Na+ channels by tyrosine kinase was examined in human uterine smooth muscle cell line, using whole-cell voltage clamp (at a holding potential of - 90 mV). Bath application of genistein, an inhibitor tyrosine kinase, decreased the fast Na+ current (INa(f)) dose-dependently. The maximal inhibition of INa(f) was 98%, and the concentration for half-maximal inhibition (IC50) was 9 microM. The effect of genistein was rapidly reversible. Daidzein, an inactive analog of genistein, had a similar inhibitory effect on INa(f). These results suggest that the fast Na+ channels in uterine sarcoma cells may be directly blocked by genistein and daidzein, i.e., their effect may be independent of tyrosine kinase inhibition.

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