Why Avoid Soy?

There are many concerns with soy; it contains many anti-nutrients and components that are toxic to humans.  The ingestion of soy has also been linked to the development of many health issues such as breast cancer, digestive issues, hypothyroidism, infertility, thyroid cancer, and many other disorders as listed in our book on page 58. There are many potential problems with soy discussed in the book including:

1. Soy causes many thyroid problems.  It is a known goitrogen—it promotes goiter or swelling of the thyroid gland.  (More about this in Chapter 5.)
2. Soy inhibits the uptake of iodine, which is used by the thyroid gland in the production of thyroid hormones.  (More about this in Chapter 5.)
3. Soy contains phytoestrogens (plant estrogens) which may disrupt endocrine function.  (More about this in Chapter 4.)
4. Soy contains large amounts of phytates (including phytic acid).  Phytic acid is the storage form of phosphate in plants.    Research has shown that phytic acid has been found to reduce the assimilation of minerals including calcium, copper, iron, magnesium, and zinc.  The fermentation process helps in neutralizing phytic acid, which is one reason why fermented soy is healthier for you.  (More about this in Chapter 3.)
5. Soy has also been shown to increase the body’s requirement for vitamin D.
6. It has long been recognized that soy consumption can cause vitamin B12 deficiency.
7. During the processing of soy, highly carcinogenic nitrates and a toxin called lysinoalanine are formed.  Also, many soy foods often contain MSG and aluminum.
8. Most soy in the United States is genetically modified (GM).  It is estimated that about half of the American soybean crop planted in 1999 carries a gene that makes it resistant to an herbicide (Roundup®) used to control weeds.  Therefore, these GM soy plants are continually sprayed with large amounts of Roundup®.  (More about GM soy can be found in Chapter 8.)
9. Soy has one of the highest percentages of pesticide contamination of any food.
10. Soy is highly allergenic and is in fact one of the top eight food allergens.  It is found as filler in so many foods that people with allergies may be at risk.  (More about soy and allergies can be found in Chapter 7.)
11. Soy contains saponins which have been show to damage the mucosal lining of the intestine or cause leaky gut.  (More about leaky gut can be found in Chapter 7.)
12. Soy contains oxalates which can prevent calcium absorption and have been linked to the development of kidney stones.