male should avoid drinking soy milk in large quantity

Some research suggests it may have negative side effects for men when consumed in large quantities...Soy milk contains isoflavones which provide many of the benefits of soy products. Isoflavones, according to the American Cancer Society, can have weak estrogen-like activity, which is the basis for why some men avoid soy milk...A Harvard University cross-sectional study published in “Human Reproduction” found that dietary intake of soy and isoflavones reduced sperm concentration in men. Although the reduction was small, it was considered statistically significant...Some research suggests that large doses of soy may decrease penile function. A certain isoflavone found in soy, daidzein, and its effects on erectile functions were studied in rats.

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