"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,” Dr. Daniel says.
“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.
To make matters worse, Americans are consuming soy in unprecedented amounts. Among the many health problems linked to a high-soy diet are:
• Thyroid problems, including weight gain, lethargy, malaise, fatigue, hair loss, and loss of libido
• Premature puberty and other developmental problems in babies, children and adolescents
• Cancer
• Brain damage
• Reproductive disorders
• Soy allergies
Most soy, perhaps about 80 percent or more, is also genetically modified, which adds its own batch of health concerns.
http://articles.mercola.com/sites/articles/archive/2008/09/04/why-soy-is-not-the-health-food-you-think-it-is.aspx