Soy became somewhat of a fad starting in the late ’70s. With the alarming rise in the numbers of people manifesting wheat sensitivities, soy was a versatile, prolific, and inexpensive substitute.
It’s also grown in popularity in the health and wellness market as an alternative source of protein and fats. Also, soy is used in processed foods as a filler (adding weight to meat and other products) and emulsifier.
“Unlike in Asia where people eat small amounts of whole soybean products, western food processors separate the soybean into two golden commodities–protein and oil. There’s nothing safe or natural about this,” explains Dr. Kaayla Daniel, author of the book The Whole Story: The Dark Side of America’s Favourite Health Food (1).
“Today’s high-tech processing methods not only fail to remove the anti-nutrients and toxins that are naturally present in soybeans but leave toxic and carcinogenic residues created by the high temperatures, high pressure, alkali and acid baths and petroleum solvents,” she continues.
The promoters of soy as a staple missed a few important facts about soy, however, that are now becoming apparent in the development of soy sensitivities.
What they missed was that in the countries in which soy is a regular part of the diet, it comes in the form of fermented soy, not the forms of soy that are presented to us in North America. This is especially true when it comes to soy products that are isolated and manufactured, such as soy protein isolate and hydrolyzed plant protein.
Additionally, the amounts we eat (specifically and generally) are much greater than in other cultures.
The Problem with Soy
All processed soy contains compounds called phytates. These compounds block mineral absorption, while other compounds in soy called trypsin inhibitors block proper digestion.
A high-soy diet is linked to (2,3,4,5):
- Thyroid problems, including weight gain, lethargy, malaise, fatigue, hair loss, and loss of libido
- Premature puberty and other developmental problems in babies and children.
- Cancer
- Brain damage
- Reproductive disorders
- Soy allergies
Plus, Dr. Daniel warns that soy can raise homocysteine levels, which in turn increases your risk of heart disease, stroke, and birth defects.
Many experts have since petitioned the FDA to retract the 1999 claims that “soy prevents heart disease” (6).
Babies and children are at a higher risk, since soy can mimic estrogen and throw off hormone balance. In fact, a Lancet study showed that the daily exposure to estrogen-imitating chemicals for infants who consume soy formulas was 6-11 times higher than adults consuming soy foods (7). What’s more, the blood concentration of these hormones was 13,000 to 22,000 times higher than natural estrogen. For an infant fed exclusively on soy-based formula, that’s equivalent to 5 birth control pills a day (8).
Infants should not be fed soy-based formula and pregnant or breastfeeding mothers should avoid soy at all costs. What’s more, soybeans contain hemagglutinins, which cause red blood cells to clump together (9).
Other Concerns
1. Genetic Modification
Over ninety percent of the soy produced in the U.S. is genetically modified (GM). These GM crops are sprayed with chemical herbicides and pesticides that they’ve been developed to resist. These chemicals (such as glyphosate) have been found to be toxic to humans.
2. Increased Risk of Breast Cancer
Soy contains high levels of phytoestrogens, chemicals found in plants that are similar to mammalian estrogen.
Since eating soy increases the amount of estrogen in the body, there is concern that large amounts can promote breast cancer.
A condition of estrogen dominance–in which there exists an overabundance of estrogen in the body consistently over time–can lead to a host of health issues including mood swings, insomnia, weight gain, infertility, and osteoporosis–for both women and men.
3. Phytoestrogens Can be Harmful
The result of regular increased levels of estrogen in males can contribute to lowered production of testosterone.
The imbalance of these hormones has been associated with erectile dysfunction, decreased libido, and gynecomastia, a condition of swollen breast tissue in men (10).
There is also evidence that high (unfermented) soy intake is directly related to low sperm count (11).
4. Preventing Nutrient Absorption
Phytic acid in soy inhibits the ability of the body to absorb minerals like iron, magnesium, calcium, copper, and zinc from the foods you eat (not just the soy).
This form of phosphorus arrests the activities of digestive enzymes like pepsin and trypsin. That is why soy affects some people by causing gas and bloating.
Many processed foods that contain soy include aluminum, a metal toxic to humans that affects kidney function.
Soy is a goitrogenic food that has consequences for thyroid function; it prevents the absorption of iodine, a necessary mineral for cellular metabolism and activation of the thyroid.
Problems with thyroid function have become increasingly prevalent in North America as the result of our diets and sedentary tendencies. The hormones produced by the thyroid control how your body uses food for energy.
Soy can be the healthy nutrient source it was purported to be–it’s the form it takes that makes the difference. Opt for the organic fermented kind.
The Fermentation Difference
The fermentation process for soy serves to break down the enzymes that not only negatively affect absorption of its considerable nutrients but can actually be potentially harmful to our bodies in significant amounts.
Tempeh, natto, and miso are fermented soy products and are a good source of protein, iron, vitamins, minerals, probiotics, and antioxidants that can help prevent the development of cancer.
Tofu, edamame, soy milk, and the soy (including that in infant formula) and soy oils used in processed foods are not fermented; below are some reasons why you may want to rethink these forms of soy in favor of the fermented kind.