Newest Research on the Dangers of Soy
The Chinese did not eat unfermented soybeans as they did other legumes such as lentils because the soybean contains large quantities of natural toxins or “antinutrients.” First among them are potent enzyme inhibitors that block the action of trypsin and other enzymes needed for protein digestion.
These inhibitors are large, tightly folded proteins that are not completely deactivated during ordinary cooking. They can produce serious gastric distress, reduced protein digestion and chronic deficiencies in amino acid uptake. In test animals, diets high in trypsin inhibitors cause enlargement and pathological conditions of the pancreas, including cancer.14
Soybeans also contain haemagglutinin, a clot-promoting substance that causes red blood cells to clump together.
Trypsin inhibitors and haemagglutinin are growth inhibitors. Weanling rats fed soy containing these antinutrients fail to grow normally. Growth-depressant compounds are deactivated during the process of fermentation, so once the Chinese discovered how to ferment the soybean, they began to incorporate soy foods into their diets.
In precipitated products, enzyme inhibitors concentrate in the soaking liquid rather than in the curd. Thus, in tofu and bean curd, growth depressants are reduced in quantity but not completely eliminated.
Soy also contains goitrogens – substances that depress thyroid function.
via Dr Mercola Newest Research on the Dangers of Soy