Re: Thyroid issue - Found the culprit

Merely guessing; a few grams of fermented soy is not a big problem.
I stay away from it as much as possible these days, both because of the GMO, but also because the omega 6 overload. Soy protein isolate I would absolutely not consume.

"How much soy do Asians really eat?
Those who dare to question the benefits of soy tend to receive one stock answer: Soy foods couldn't possibly have a downside because Asians eat large quantities of soy every day and consequently remain free of most Western diseases. In fact, the people of China, Japan, and other countries in Asia eat very little soy. The soy industry's own figures show that soy consumption in China, Indonesia, Korea, Japan, and Taiwan ranges from 9.3 to 36 grams per day. (1) That's grams of soy food, not grams of soy protein alone. Compare this with a cup of tofu (252 gms) or soy milk (240 gms). (2) Many Americans today think nothing of consuming a cup of tofu, a couple glasses of soy milk, handfuls of soy nuts, soy "energy bars," and veggie burgers. Infants on soy formula receive the most soy of all, both in quantity and in proportion to body weight"
http://www.vaccinetruth.org/soy_formula.htm

For males, you also have to consider the phyto estrogen level of soy. Also a very high manganese contents, may cause a disruption in iron uptake / utilization.
http://chestsculpting.com/the-truth-about-soy-and-man-boobs/
http://lpi.oregonstate.edu/infocenter/minerals/manganese/