Free t4

Less than 0.05% of Total Thyroxine (T4) is free or unbound. The hormone is made in the thyroid gland and is the precursor to T3. Production of T4 is dependent on levels of iodine, co factors like B6, Biopterin, Copper, Zinc, Vitamins B2, B3 and A. Considered by mainstream when combined with TSH to be the gold standard for assessing thyroid function., Levels are assessed to identify thyroid status (hypo and hyper), Iodine sufficiency as well as protein status and liver function.

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 +

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The FDX Method

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