Free t3

The portion of triiodothyronine (T3) that is not bound and represents approximately 10% of circulating T3 in the blood. T3 is converted from T4 and the majority occurs in the liver and kidneys. The conversion process is dependent on Selenium and bile levels. Levels can be used to assess Hypo and hyper thyroid status, T4 to T4 conversion efficacy, Selenium sufficiency, and Iodine sufficiency.

Available Tests

FDX 00


Full Biomarkers +
FDX 34


Full Biomarkers +
FDX 21


Full Biomarkers +
FDX 03


FDX 32


Full Biomarkers +
FDX 18


FDX 26


Full Biomarkers +
FDX 25


Full Biomarkers +
FDX 33


Full Biomarkers +

Patient Test Info Sheet

Example Snapshot Report

The FDX Method

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Additional Resources