The Effect of Phytoestrogens on Males

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Phytoestrogens are plant-based compounds found in foods such as soybeans, soy milk, kudzu root, and flaxseed, which happen to mimic the structure of estrogen

There has been a lot of confusion in the media about whether or not phytoestrogens actually have estrogenic, or estrogen-promoting, properties. 

Studies show that these phytoestrogens do not increase or alter estrogen levels or activity in men.

In fact, phytoestrogen-rich plants may actually support reproductive and overall health in men.

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Can Phytoestrogens Impact Male Fertility?

The primary reason many people avoid phytoestrogens is that they’re concerned it may contribute to male infertility. However, this is a myth — there is no reliable evidence to support this theory.

Studies indicate that phytoestrogen intake, even in infant formula, does not have a notable impact on testosterone levels or any other aspect of male fertility.

Health Benefits of Phytoestrogens for Men

Phytoestrogens from plants may provide health benefits for:

  • Reproductive health
  • Heart health
  • A role in weight loss
  • Hormone-dependent tumors
  • Bone and skin health
  • The immune system

These compounds actually have a very different effect than estrogen. In many cases, they will block an over-stimulated estrogen receptor, reducing any negative effects that estrogen may be having on the body. 

And in other cases, they actually improve estrogen-related activity, such as in the case of soy isoflavones. Ipriflavone, a soy isoflavone derivative, has been shown to improve bone density in people with osteoporosis.

Phytoestrogens and Breast Cancer

Additionally, the incidence rate of breast cancer in Asia is almost half of the incidence in Europe. Breast cancer is a cancer type that is estrogen-dependent in 8/10 cases

If phytoestrogens were actually stimulating estrogen receptors in a negative way, that theory would hold that people who eat more soy-containing foods would develop breast cancer at a much higher rate. Korea and Japan, two countries in the world that consume the most soy, have some of the lowest breast cancer incidences in the world.

It’s much more likely that phytoestrogens actually incur a protective, modulatory hormonal effect rather than a harmful one.

GMO vs. Non-GMO Soy

It’s estimated that up to 94% of the soy produced in the U.S. is GMO (genetically modified) to be resistant to glyphosate (Roundup), a pesticide and known hormone-disrupting chemical. This means that up to 94% of the soy in the U.S. is heavily sprayed by this known toxin.

Glyphosate has been shown in studies to cause harm to the neurological, reproductive, and immune systems in animals. The International Agency for Research on Cancer classified it as “probably carcinogenic to humans” in 2015. 

All this is the say, if you’re eating soy in the U.S., please only buy organic, for the safety of your hormones, and all other systems in your body.

Do Phytoestrogens Cause Any Adverse Effects?

Although there are several myths about these estrogen-mimicking plants, the evidence suggests that they do not cause any significant adverse effects on human health. 

There is limited evidence that consuming these compounds if your iodine levels are very low may contribute to negative health impacts, but these results are mixed.

Research has provided proof that phytoestrogens do not cause issues with thyroid function in healthy people, male fertility, or testosterone production.

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