Why Does Soy Reduce Estrogen Levels In studies?

Soy is widely known in health circles as pro-estrogenic and feminizing and men are recommended to avoid it. If that’s actually the case, can anyone explain why serum estrogen levels actually decrease in soy-supplemented groups in studies in both men and women? And why is there an inverse relationship between hormone dependent cancers such as breast and prostate cancer (I suppose all cancers are hormone dependent) and soy consumption? Here are just some of the studies I’m talking about:

https://www.ncbi.nlm.nih.gov/pubmed/8770469 - 36-oz of daily soymilk consumption for a month significantly decreased serum 17 beta-estradiol levels in premenopausal women.

https://www.ncbi.nlm.nih.gov/pubmed/9839524 - Estrone and estradiol levels were decreased by 23% and 27% at the end of the study in the soy milk supplemented group in Japanese women. The change in estrone and estradiol levels was minor in the control, non-soy group.

https://www.ncbi.nlm.nih.gov/pubmed/11303585 - Serum estrone concentrations  decreased in the soy-supplemented group in Japanese men. There was no change in testosterone levels in both the soy group and the control group.

Is it that the estrogen circulation in blood decreases from soy but estrogen level inside the cell increases? Is that why soy is so widely considered as ‘estrogenic’?

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  • soy or Glycine max, is a legumus plant and humans tend to eat the seeds from the seed pods and becuase we are not anatomical predominant seed eaters the seed of the soy is not so suitable. once the seed is germinated the young stalk and the leafs are easier to digest for humans and this is probobly the stage it should be consumed for humans.

    soy contains phytohormones, not the same as animal homones, the article below writtes about how the results can vary between race (etnicity) and other factors involved.


    Straight Talk About Soy
    Soy is exalted as a health food by some, with claims of taming hot flashes, warding off osteoporosis, and protecting against hormonal cancers like br…
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