Can drinking soy milk affect your maleness?

Last updated on September 24, 2020


There are a lot of articles online about soy milk increasing estrogen and decreasing facial hair is it true or does it not even affect the body at all? At home, I drink soy milk because my sister can’t drink milk, so I drink it too and I don’t mind the taste.


From Silk, a maker of soy milk:

Contrary to many misleading published accounts, soy does not contain the hormone estrogen. Soy does contain isoflavones, also known as phytoestrogens or “plant estrogens.” While the chemical structure of isoflavones is similar to estrogen, the two function very differently in the body.

Claims that soy causes feminizing effects in men or boys are not supported by scientific evidence. A review of over 150 clinical studies found that isoflavone and soy food consumption showed no effect on testosterone or estrogen levels, sperm count, breast size, or erectile function in men.

[Does soymilk contain estrogen? Can young boys drink it?]

Dr. Andrew Weil, a medical doctor involved in selling health supplements, made these observations:

When you consider that millions of men in China, Japan and other Asian countries have had soy foods in their daily diets from earliest childhood, you can appreciate that the plant estrogens they contain have no discernible effect on male sexual development, and no feminizing effects at all. Given the huge populations of Asian countries there’s no reason to think that soy affects male fertility, either.

However, concerns in the Western world about the effects on boys and men from eating soy foods have been raised repeatedly and addressed in numerous laboratory and population studies. Researchers at the University of Pennsylvania surveyed men and women who, as babies, were given soy-based formulas to see if any of them had sexual, fertility or hormonal problems; they were then compared to a matched group raised on cow’s milk formula. The only discrepancies noted were some minor menstrual complaints among the women (their periods lasted one-third of a day longer and they reported slightly more menstrual pain). Results were published in the August 15, 2001, issue of the Journal of the American Medical Association.

In March 2002 the Journal of Nutrition published results of a survey of men consuming soy foods or supplements containing 40-70 milligrams of isoflavones (the phytogenic components). None of the studies showed that consuming soy had any effects on reproductive hormones or semen quality, both changes that you might expect to see before any overt “feminization” would occur.

[Can Soy Feminize a Boy?]

Dr. Walter Willett of the Harvard School of Public Health says much the same:

Soy and soy milk do contain molecules that interact with estrogen receptors and therefore have weak, estrogen-like effects. However, because these effects are weak, the molecules may actually act like anti-estrogens by competing with the body’s natural estrogens when estrogen levels are high. For this reason, soy products have been hypothesized to reduce the risk of breast cancer. The evidence isn’t conclusive, but there’s some suggestion that soy consumption during childhood may reduce risk of breast cancer later in life. Soy milk or other soy products may also reduce risk of prostate cancer, but again nothing conclusive — and we don’t know about the effects of consumption during childhood on prostate cancer risk.

[Children and soy milk]

When finding information online you need to consider the sources of the information. Who is saying this? What makes them an authority on this subject? Are they backing up their claims? Just because someone says something, it doesn’t make it true.