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Soy’s Dirty Secret, Part 2

In my last article, we covered some of soy’s little-known health issues. In my next article, we’ll talk about the healthiest forms of soy. But today, we’re going to discuss soy’s “dirty secret.”

I’ll start right out by saying that soy alone may not cause this problem for everyone. But when you look at soy in the big picture, the possibilities are alarming.

I’m talking about phytoestrogens. These are chemicals in plants that mimic estrogen, the “female” hormone. And soy is loaded with them.

The Feminization of America

Soy contains a number of phytoestrogens, but the most abundant – and best known – are the isoflavones daidzein and genistein. Adding significant amounts of these chemicals to your diet can create problems for both men and women. But for the moment, we’ll look at the problems for men.

For example, animal studies show that soy phytoestrogens can have a negative impact on male sex hormones.

A study at the University of Maryland found that soy isoflavones inhibit normal male sexual behavior and have a negative impact on reproduction.1 And when Johns Hopkins researchers fed soy isoflavones to female mice, their male offspring were smaller and less aggressive than normal mice. The researchers called the results “persistent demasculinization.”2

This should come as no surprise, since male-to-female transsexuals use estrogen therapy to minimize their masculine traits. And with the explosion of soy in the food market, virtually all American men are now on estrogen therapy.

But the problem reaches much further than that. It’s gone global… and I’ll explain why in a moment.

Soy Is Just the Tip of the Estrogen Iceberg

Doctors have known for years that male fertility has shrunk worldwide.

Back in 1992, Danish researchers used the World Health Organization’s Medicus database – along with Center for Disease Control’s Medline database – to research male fertility around the world. The results could be a plot for a science fiction movie.

Covering nearly 15,000 men over a 50-year period, the results showed a steady decline in sperm quality. Sperm count declined by more than 40% between 1940 and 1990. Even worse, as sperm counts dropped, genital and urinary “abnormalities” in men increased.3

The message is clear: Men are becoming less masculine. And the reason may be all around us. Our world is over-run with chemicals that act like estrogen… and soy is just the tip of the iceberg.

Estrogen Is Everywhere

Taken alone, soy’s feminizing effects might not be so bad. But man has created a world full of estrogen-like chemicals. In fact, they’re so common, we even have a name for them: xenoestrogens.

Here are just a few of the sources of these chemicals that Tufts University researchers have identified:

  • Insecticides
  • Plastic dishes and other common laboratory utensils
  • Plastic water bottles
  • The liners used in cans of food
  • Detergents
  • Dental sealants and composites
  • Spermicides and condom lubricants
  • Disinfectants4

For just a moment, picture the shelves of water bottles at your local supermarket. Now imagine how many supermarkets have identical shelves loaded with these bottles. And how many “tin cans” are there in the world today?

Now add in detergents, insecticides and all the rest. All of them add estrogen-like chemicals to your body… and then you toss soy on top of it. It’s like telling an obese man who lives on a diet of cake and candy bars to go ahead and eat a cookie. “After all, it’s just one cookie.”

But that “one cookie” could push you over the edge. Consider this: Depending on the brand, a 6-ounce serving of tofu may contain 44.2 – 53.3 mg of soy isoflavones. Koreans eat a lot of soy, but that’s triple the 15 mg per day in the average Korean diet!5, 6 So don’t look to the Far East for a way out.

But you shouldn’t panic, because you can limit your exposure to excess estrogen.

Three Simple Steps to Better Hormonal Health

Whatever you do, don’t throw the baby out with the bathwater. Here are three easy steps that will help you take advantage of the health benefits of soy, while avoiding the risks.

Step 1: Eat Organic. You can cut your pesticide exposure significantly simply by eating organic fruits and vegetables. Pesticides are a major source of environmental estrogens. Switching to organic produce will cut your exposure – and your risk.

Step 2: Avoid bottled water. Install a good quality water filter in your sink – or use a filtration pitcher. Both options will cut your exposure to xenoestrogens… and you’ll save a bundle of money, too.

Step 3: Skip the tofu. Tofu is the worst offender when it comes to isoflavones. Stick to fermented soy products and you’ll get soy’s most important health benefits, while avoiding a lot of the risks.

The bottom line is that soy does offer health benefits, but how you get your soy really matters. In part three of this series, you’ll discover why fermented soy foods are your best – and healthiest – bet.

Best Life Herbals Wellness Team
Best Life Herbals


1 Ottinger MA, et al. Neuroendocrine and behavioral effects of embryonic exposure to endocrine disrupting chemicals in birds. Brain Res Rev. 2008 Mar;57(2):376-85. Epub 2007 Sep 19.
2 Wisniewski AB, et al. Perinatal exposure to genistein alters reproductive development and aggressive behavior in male mice. Physiol Behav. 2005 Feb 15;84(2):327-34. Epub 2005 Jan 12.
3 E. Carlsen, et al. Evidence for decreasing quality of semen during past 50 years. BMJ  1992;305:609-613 (12 September), doi:10.1136/bmj.305.6854.609.
4 Sonnenschein C and Soto A. An updated review of environmental estrogen and androgen mimics and antagonists. The Journal of Steroid Biochemistry and Molecular Biology, Volume 65, Issues 1-6, April-June 1998, Pages 143-150.
5 Dwyer JT, et al. Tofu and soy drinks contain phytoestrogens. J Am Diet Assoc. 1994 Jul;94(7):739-43.
6 Kim JS and Kwonb CS. Estimated dietary isoflavone intake of Korean population based on National Nutrition Survey. Nutrition Research, Volume 21, Issue 7, July 2001, Pages 947-953.

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