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Learn · Thyroid

Reverse T3

Measured in ng/dL

An inactive mirror-image of your active thyroid hormone. Your body makes more of it when it wants to slow metabolism down.

What the numbers mean

These are the ranges BioForge works to. They are not the same as a lab's reference range, which is built from the general population rather than from people who feel well.

Low
<9.2
Optimal
12–18
High
>24.1

What moves Reverse T3

Rises with calorie restriction, aggressive dieting, overtraining, illness, high cortisol, and low ferritin or selenium. High reverse T3 with normal TSH is the classic picture of a body under stress choosing to bank energy — it usually resolves by fixing the stressor, not by adding thyroid medication.

Related markers in Thyroid

This page is educational and is not medical advice. Ranges are general and do not account for your history, medications or symptoms — a single number never decides a protocol. Your results are interpreted by a licensed clinician alongside everything else about you. Back to the Learning Center

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Every BioForge protocol starts from your own bloodwork. The first 15-to-30-minute call is free.

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