Thyroid: Why TSH Alone Misses Most of the Problem
One number is used to rule the whole system in or out, and it sits two steps upstream of anything you would actually feel.
Thyroid
Thyroid dysfunction is frequently diagnosed on a single number and frequently missed for the same reason. Conversion of T4 to active T3 depends on selenium, zinc, iron and a liver that is not overloaded, and none of that appears on a standard TSH test. These pages cover the full panel and what governs each part of it.
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