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Soy and feminine side effects

We’ve all heard it: Men shouldn’t eat soy because it gives them female characteristics.

But is it true? No, it’s not. How do I know? Because science says so.

Despite this, there is a big misconception going around that soy will make men develop female traits. These claims include, but are not limited to, female breasts, small penises, infertility, lower testosterone levels and much more.

Estrogen in women

In case you didn’t know, estrogen in women are what make up the primary female sex hormones. I mention this because in soy, there’s also something called estrogen.

Eating soy however, is very different from pumping your body full of female sex hormones.

Considering that soy has been consumed for centuries (especially in Asia and the likes), and that I don’t remember reading much about asian men with boobs, it stands to reason—science or not—that soy will not turn men into women.

Estrogen in soy

Unlike the female sex hormones that make up estrogens in their bodies, estrogen in soy is a different breed alltogether, namely phytoestrogens, or simply plant estrogens.

It is likely because of this—namely that people hear the word estrogen and decide to sweep it all under the same rug—that the myth of soy and man boobs were born.

So to be very clear; estrogen in women is not the same as estrogen is soy.

Scientific findings

There’s a lot of data available on this topic, and based on my research I don’t see this myth holding water. But please, go out and see for yourself. Below are a few studies to get you started.

“(..) neither isoflavone supplements nor isoflavone-rich soy affect total or free testosterone (..)”

“(..) there is essentially no evidence from the nine identified clinical studies that isoflavone exposure affects circulating estrogen levels in men.”

“Clinical evidence also indicates that isoflavones have no effect on sperm or semen parameters (..)”

“(..) findings from animal studies suggesting that isoflavones increase the risk of erectile dysfunction are not applicable to men (..)”

“(..) data indicate that isoflavones do not exert feminizing effects on men at intake levels equal to and even considerably higher than are typical for Asian males.”

Soybean isoflavone exposure does not have feminizing effects on men: a critical examination of the clinical evidence

“Soyfoods have been a part of Asian diets for centuries and there has never been any indication that they affect reproduction in these populations. Current research on this issue supports what history has long shown.

Vegan for Life: Everything You Need to Know to Be Healthy and Fit on a Plant-Based Diet

In conclusion

Stop worrying; you won’t become a woman if you continue eating soy.

Both science and the billions of people who regurlarly consume soy are proof of that.

If you want a slightly broader discussion around the safety of soy, please pick up the book Vegan for Life: Everything You Need to Know to Be Healthy and Fit on a Plant-Based Diet.

For the animals,

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