The soy and estrogen myth: don’t believe the hype

There have been a lot of rumors floating around these days involving soy and why it’s bad for you. How much of this is propaganda spread by people who would rather you ate animals is arguable, but there are some solid studies out there that show soy is actually beneficial in a variety of ways for both women and men.

breast cancer

The soy-breast cancer controversy: does soy increase breast cancer risk?

Unlikely. Check out this factoid from the American Cancer Society, “..while isoflavones may act like estrogen, they also have anti-estrogen properties. That is, they can block the more potent natural estrogens from binding to the estrogen receptor. In addition, they stop the formation of estrogens in fat tissue and stimulate production of a protein that binds estrogen in the blood (to make it less able to bind to the receptor). They also have anti-oxidant and anti-inflammatory properties and work in other ways to reduce cancer growth.” In English: when estrogen reaches the estrogen receptors in breast cells, it can cause tumor growth; soy appears to prevent the meeting of the two.

Some studies have shown that women who eat a lot of soy actually have fewer instances of breast cancer; and breast cancer survivors who participated in a study on soy and breast cancer recurrence found that women who consumed soy regularly had a 25% lower recurrence rate. And let’s not forget about Asian women, who eat more soy than most other women — their breast cancer risk is 24% lower than other women.

Source: American Cancer Society

Soy and a feminizing effect on men

If you read that Men’s Health story that came out a few years back, where a couple of men claimed they started growing breasts and exhibiting symptoms of sexual dysfunction, I hope you took it with a grain of salt. These men were extreme case studies, as one had a metabolic disorder, and another was drinking 3 quarts of soy milk per day. I think it’s safe to say that drinking that quantity of any milk, or even any kind of beverage other than water, would come with some negative health effects.

In fact, a 2009 study found that when men ate soy, it seemed to reduce their risk for prostate cancer by up to 26%. Most of the studies done in the past to see if soy contributed to sexual dysfunction and other “feminizing” side effects were performed on rodents; and seeing as humans and rodents don’t metabolize isoflavones in the same way, those studies cannot make true statements about the effects of soy on men. You can read the clinical evidence for yourself.

Source: The ZocDoc Blog

Benefits of soy

  • The isoflavones in soy have a non-hormonal effect on the body, which helps regulate cell growth. This protects against some cancers and can help regulate cholesterol levels.
  • Soy can help lower blood pressure.
  • It is high in protein and lower in saturated fat than some animal alternatives.
  • Soy is high in fiber (which contributes to lower cholesterol).
  • Tofu is high in omega 3’s and calcium (and if you are on a dairy-free diet, getting calcium wherever you can is very important).

Source: Dr. Oz

The best kind of soy to eat

  • Fermented soy, in the form of miso, tempeh, natto and soy sauce, are easy to digest and are full of probiotics. Additionally, the nutrients in fermented soy are more readily available than in other forms.
  • Edamame
  • Tofu

Soy foods to avoid

  • GMO soy. You want to make sure what you are eating is not genetically modified. Most packaged foods that contain soy as an additive are using GMO soy. Thankfully, I’ve found that the only tofu available for sale at my grocery store says “non-GMO” right on the front of the package. 
  • “Processed” soy products. This includes most (if not all) brands of soy milk, by the way. With any processed food, the nutrients have been stripped from the original product, and you are eating food that gives you very little nutritional value. Not to mention all of the added ingredients and preservatives that are bad for you. Your food shouldn’t have to have synthetic vitamins added to it in order to be “healthy.”

Precautions to take with soy:

It is best not to take your thyroid medication within 2-3 hours of eating soy, because it may interfere with absorption. Also, if you have an under active thyroid, it should be noted that soy is a “goitrogen” food, and should be limited to one serving per day. This means that if you eat too much soy, or other goitrogens like corn and sweet potatoes, it has the potential to cause your thyroid gland to enlarge. These foods do not cause hypothyroidism, however; so if you don’t have a thyroid problem, you should be A-ok to eat soy in larger amounts.

Source: Dr. Weil

Get the word out! Please pass along this infographic about soy:

Infographic: Rumors About Soy

Soy is healthy! Soy is good for you!

As you can see, the health benefits of soy far outweigh any negative health effects for a majority of the population. I hope that this knowledge will be circulated so that the rumors surrounding soy can be dispelled. This information should come as a relief to any vegetarians or vegans out there that have been concerned about their own levels of soy intake. Don’t worry, guys, keep on keepin’ on!

Have you been avoiding soy because of the hype?