Tofu, whole soybeans, soy milk, and soy nuts are readily available in most grocery stores and are usually used as meat/dairy substitutes and as snack items. However, there has been an increased focus on these products because of recent studies that suggest that soy products have high amounts of estrogen in them, may lead to infertility, and cause thyroid issues. Women have been warned to avoid all soy products because of these suggestions.
The most prominent hype against soy is the the suggestion that soy products may cause infertility, ultimately behaving like a birth control pill. This suggestion likely derives from the fact that soy does contain isoflavone phytochemicals, which is a type of plant estrogen (phytoestrogen). These estrogenic compounds are found in various other types of plant matter, such as garlic, grains, carrots, apples, hops (yes, this means beer!), coffee, and cherries. Phytoestrogens are significantly weaker than the estrogen produced naturally by humans, and do not compare to the synthetic estrogen that is put in birth control pills. A human being would have to consume about 100 grams of tofu per day for an extended period of time in order to be seeing hormonal imbalances due to their soy intake. The average American consumes around one or two grams of soy products per day.
Soy has been thought to inhibit the absorption of medicine given to patients who suffer from hypothyroidism, but no conclusive studies have been published on the matter. It has been suggested that consuming soy products while taking synthetic thyroid hormones inhibits the body's ability to effectively utilize the medication, but the same suggestions also apply to high-fiber foods, iron/calcium supplements, and antacids.
Here are some other important factors to consider when mulling over 'to eat or not to eat':
- Some of the most popularly sited research studies are conducted on non-human organisms such as rats, mice, sheep, and even cheetahs. Ethical controversies prevent certain tests to be conducted on humans, but assuming that test results in a different species will mirror human results is a controversial idea.
- Most Asian countries, all of which rank as being the most healthful populations in terms of overall wellness, consume significantly larger amounts of soy products than Western countries, averaging at about eight to nine grams of soy (mostly tofu) per day.
- Contrary to popular belief, soy contains all essential amino acids found in meat products. This makes soy a great meat substitute.
- Not all studies that claim to find a correlation are due to causation. Thus, understanding the difference between correlation and causation is of paramount importance when considering research studies done on this topic. To give an example: major cities have reported extremely high ice cream sales during the summer. Murder/crimes rates raised just as high during the same time period in those cities. The variables ice cream and murder/crime are correlated, but the correlation is not due to causation. Meaning, increased ice cream sales did not cause higher murder/crime rates, and vice versa.
Food for thought. What do you think?