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Soy Isoflavones

Soy Isoflavones, usually Genistein and Daidzein, are bioflavonoids found in soy products and other plants that are able to interact with various hormones such as estrogen. They appear to be healthy, and are not anathema to young men and testosterone levels.

Our evidence-based analysis on soy isoflavones features 112 unique references to scientific papers.

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Summary of Soy Isoflavones

Primary information, health benefits, side effects, usage, and other important details

Soy isoflavones (Genistein and Daidzein) are compounds found in a wide variety of foods, but mostly soy, that affect a wide-variety of body systems. They seem to mimic the female hormone estrogen to a degree (although slightly different).

They have been implicated in both reductions and increases of breast cancer risk, and generally are good at cardioprotection from reducing lipoprotein levels and are seen as good for bone health in the aging as well.

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How to Take

Medical Disclaimer

Recommended dosage, active amounts, other details

Many anti-carcinogenic effects of genistein are seen in the range of 10-20mg/kg bodyweight a day. Epidemiologically, this dose is also associated with reduced lipoprotein levels.

In vitro studies on glucose and muscle cell metabolism showing a nutrient partitioning effect at 20-30uM correlate to a dietary intake of 200-300mg/kg bodyweight (assuming the 1uM circulating serum levels per 10mg/kg BW intake noted.[1])

Things to Note

Is a Form Of

Primary Function:

Also Known As

Genistein, Genistin, Daidzein, Daidzin, Equol, Dihydrogenistein, Dihydroglycitein, Glycitein, Glycitin

Do Not Confuse With

Soy (the food product), Soy Lecithin (another molecule found in soy)

Goes Well With

  • Weight-bearing Exercise and osteopenia/osteoporosis prevention

  • Biochanin A (aromatase transcription)

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Click here to see all 112 references.