The Claim

Rapid weight loss induced by semaglutide suppresses hepatic type-1 deiodinase activity and increases type-3 deiodinase activity, resulting in reduced conversion of thyroxine (T4) to triiodothyronine (T3) and increased production of reverse T3 (rT3), contributing to euthyroid sick syndrome.

Source: Euthyroid Sick Syndrome Precipitated By Rapid Weight Loss Following Semaglutide Initiation: A Case Report

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
30score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

Semaglutide-induced rapid weight loss reduces the liver's production of the active thyroid hormone T3 and increases the production of the inactive form rT3, altering thyroid hormone metabolism in a pattern associated with euthyroid sick syndrome.

See the scientific wording

Rapid weight loss induced by semaglutide may suppress hepatic type-1 deiodinase activity and increase type-3 deiodinase activity, leading to reduced conversion of thyroxine (T4) to active triiodothyronine (T3) and increased production of inactive reverse T3 (rT3), contributing to euthyroid sick syndrome.

Why this might work

When body fat drops quickly, the liver makes less of the enzyme that turns thyroid hormone into its active form, while other tissues make more of the enzyme that turns it into an inactive form. This causes less active hormone and more inactive hormone in the blood, slowing down metabolism to save energy.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Euthyroid Sick Syndrome Precipitated By Rapid Weight Loss Following Semaglutide Initiation: A Case Report

    When this woman lost weight quickly using semaglutide, her body slowed down thyroid hormone activity to save energy — making less active T3 and more inactive rT3, which is a normal survival trick during big calorie loss.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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