Free T3 vs Reverse T3
Free T3 is the active thyroid hormone. Reverse T3 is the inactive isomer produced during stress, illness, or caloric restriction. The Free T3 / Reverse T3 ratio reveals conversion quality and is decisive when TSH and Free T4 look normal but symptoms persist.
Free T3 is decisive for active thyroid status and symptom correlation.
Reverse T3 is decisive for ruling out non-thyroidal illness, chronic stress, or caloric-restriction-driven conversion suppression.
Educational. Final pathway selection is provider-reviewed via synchronous video consultation against your biomarkers, history, and goals.
Frequently asked
What is a healthy ratio?
The ratio is interpreted by the reviewing provider against symptoms and the rest of the panel — it is not a single number.
Will TSH-only catch this?
No — TSH-only cannot detect conversion defects.
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The adaptive assessment maps your symptoms, history, and goals to candidate pathways — and routes you into provider review.
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