Women who are trying to conceive may want to heed the following: Avoid eating too much soy. According to a study involving humans, a compound found in soy known as genistein has been found to impair sperm as they swim toward the egg. Even tiny doses of the compound in the female tract could destroy sperm.

What's more, researchers explain avoiding soy around a woman's more fertile days of the month might actually aid conception.

Genistein can be found in all soy-containing products, including:

• Soy milk
• Many vegetarian foods
• Some pre-packed meals and pizzas

Running Tests

Researchers tested what happened to human sperm when it was exposed to genistein in a dish in the laboratory: The soy chemical was found to create a premature reaction in the sperm, forcing them to peak long before they could fertilize an egg.

In real life, this does not usually occur until the sperm have been inside the female for some hours and are close to completing their long swim toward the egg. Without the presence of genistein around a woman's womb, sperm would peak as they should--far closer to completing their journey to the egg.

Moreover, what was surprising and telling about soy's harmful effects on human health was that it took smaller doses of genistein to create infertility problems in human females than in mice.

Based on the findings, a spokeswoman for the Vegetarian Society said that for anyone trying to become pregnant, avoiding soy products for a few days a month is worth a try ... even if there is a slim chance it will aid in fertility.

BBC News June 21, 2005

Dr. Mercola's Comments:

Traditionally, soy is viewed as having many health benefits, but there is increasingly strong scientific support that this may not be the case. When reviewing the effects of soy consumption in your body, it's usually important to consider the difference between fermented and non-fermented versions of this food. Fermented soy products include: Miso Soy Sauce Natto Tempeh Non-fermented soy products include: Tofu Soy milk Soy hot dogs and other "meatless" products made with soy or textured vegetable protein (TVP), which is usually soy based Soy yogurt and ice cream Soy protein While non-fermented soy products contain a number of potentially health-disrupting "anti-nutrients", such as phytic acid, the fermentation process drastically decreases the levels of these components. The fermentation process also aids in liberating otherwise difficult to digest nutrients in the soybean, making them more available for absorption. While in most cases fermenting soy makes it an acceptable food, in light of the above study, this, unfortunately, does not appear to be the case for women who are trying to conceive. Studies have shown isoflavones like genistein are among the nutrients whose bioavailability actually increases when the soy food they come from is fermented. In other words, if you ferment a soy product, the genistein becomes more readily absorbed. If you are having difficulties conceiving, aside from avoiding soy I strongly recommend reading an article I ran in 2004 about some of the natural alternatives available these days for fertility management. Related Articles: The Truth About Soy How Safe are Infertility Treatments? Sleep Debt Affects Female Fertility Too