I should point to the second paragraph which is why my dowsing continually shows that the Thymus is the ONLY effective way to convert T4 to T3..the other pathways are too polluted
A large majority of the thyroid hormone secreted from the thyroid gland is T4, but T3 is the considerably more active hormone. Although some T3 is also secreted, the bulk of the T3 is derived by deiodination of T4 in peripheral tissues, by the enzyme thyroid peroxidase especially liver and kidney.
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The enzyme thyroid peroxidase, converts T4 to T3 and is blocked by mercury in the body, primarily from dental mercury Amalgam fillings and thimerosol, a mercury preservative found in vaccinations and other medicines. Genistein and daidzein from soy also inactivate thyroid peroxidase enzyme.In the case of T4 and T3, more than 99% is normally protein-bound in the blood. Less than 1% is free. Only the free hormone exerts biologic activity. The protein-bound hormone is inactive.