Soy products have long been praised as a great source of protein. For vegetarians and those looking for alternatives to meat, tofu has become a dietary staple. Unfortunately, research in recent years has tipped the scales on this once-praised food—from being something that’s “good for you” to something that can cause serious damage to your health and well-being.

A Long and Profitable History

For more than 5,000 years, soy has been a staple in several Asian countries. Even tofu traces its roots to second-century China. Europe was introduced to soy in the 1700s and the U.S. in the 1800s. But it wasn’t until World War II that soy began to be cultivated on a large scale in the U.S.—where it’s now one of the most heavily produced crops.

According to SoyStats (2007), soybeans were planted on 75.5 million acres in 2006, producing a record 3.188 billion bushels. The 2006 crop value exceeded $19.7 billion, with $8.9 billion in exports. Domestically, soybeans provided 75% of the edible consumption of fats and oils in the U.S. In short, the soy industry is a multi-billion-dollar machine—well-organized and heavily funded.

A Difference of Opinion

Ask the American Soybean Association and they’ll call soy a “miracle crop”—a world leader in protein and oil production. It’s found in everything from baby foods, cereals, noodles, and cheese to pancakes, mayo, and even gravies.

But speak with the people at Soy Online Services (http://www.soyonlineservice.co.nz) and you’ll get a very different story. According to them—and many independent health professionals—soy isn’t fit for human consumption. In fact, it may be downright toxic.

Toxic to Your Health

Research over the last decade has revealed links between soy consumption and a wide range of health conditions: infertility, breast cancer, hypothyroidism, thyroid cancer, and even brain atrophy. What’s more alarming is that it doesn’t take much—just 30 grams (about 2 tablespoons) per day may be enough to cause harm.

What’s Wrong with Soy?

Soy contains:

• Phytic Acid – Reduces the body’s ability to absorb calcium, magnesium, copper, iron, and zinc.
• Trypsin Inhibitors – Interfere with protein digestion and may cause pancreatic disorders.
• Phytoestrogens – Disrupt endocrine function; linked to infertility and breast cancer.
• Antithyroid Agents – Can cause hypothyroidism and potentially lead to thyroid cancer.
• Toxic Byproducts – Processing soy results in lysinalanine and nitrosamines, both considered toxic and/or carcinogenic.
• Aluminum – Present in high levels, toxic to the nervous system and kidneys.

Soy also increases the body’s requirement for:

• Vitamin D
• Vitamin B12 (due to analogs in soy that are not absorbable)

The Scientific Evidence

• Hawaiian Study (1999) – Dr. Lon White found that two or more servings of tofu per week were associated with accelerated brain aging.
• Japanese Study (1991) – Found high thyroid cancer rates in people consuming just 30 grams/day. Within a month, test subjects showed significant decreases in thyroid-stimulating hormone levels.
• Swiss Federal Health Service – Issued a warning on soy baby formula, stating that the isoflavone levels equated to giving an infant the hormonal equivalent of 10 birth control pills per day. Over the course of a year, that totals 100 “Pill-equivalents.”

How Much Is Too Much?

Studies suggest that 30 grams of soy can be enough to negatively impact adult health. For babies and children, soy should be completely avoided. Adults still consuming soy should be aware of the following equivalents:

• Soybeans & Flours: 0.3–0.7 oz.
• Tofu: 1.8–3.9 oz.
• Soy Milks: 5.3–8.5 oz.
• Miso: 1.2–1.6 oz.
• Soybean Sprouts: 2.8 oz.

Final Thoughts

Like the old football adage says: the best defense is a strong offense. Protect yourself by educating yourself. Read labels, avoid or severely limit soy-based foods, and seek out alternatives. It’s not always easy—soy is in everything—but awareness is your best tool.

Don’t be discouraged. Yes, there are dangers. But you can still eat well, live strong, and take charge of your health. Hopefully one day, food manufacturers will wake up—but until then, we have to be relentless in protecting ourselves and those we care for.