Q:  An article I read states that the thyroid can be affected by excessive soy product consumption. What is excessive?

A:  The excessive amount of course would depend on each individual and I would always mention that. Some may be able to have more and others may be affected by the amount listed below.

Research shows that just 40 mg of Isoflavones per day, the equivalent of one serving of a soy food, equals the typical Asian Diet.

That's about 3 TBSP of Soy Powder or 1.5 ounces of Tofu.

So, eating lots of Soy is not beneficial, too high an intake especially in supplements - can turn off your thyroid and interfere with your hormones, especially estrogen.

It's a classic example of Soy being beneficial in moderate amounts and harmful in larger amounts, just like estrogen.

So use common sense.