The Claim

In pregnant C57BL/6NCrl mice, thyroid hormone treatment increases the pregnancy-associated rise in fibroblast growth factor 21 (FGF21), and adipose tissue does not undergo thermogenic activation, indicating that FGF21 elevation occurs independently of thermogenic changes in adipose tissue.

Source: Pregnancy negates thyroid hormone-induced pyrexia.

What the research says

Supports is higher

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

Supports
20score
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

In pregnant mice, thyroid hormone increases levels of a metabolic protein called FGF21, while fat tissue does not become heat-producing, showing that FGF21 rises without heat production in fat.

See the scientific wording

In pregnant C57BL/6NCrl mice, thyroid hormone treatment amplifies the pregnancy-associated rise in fibroblast growth factor 21 (FGF21), while adipose tissue remains non-thermogenic, suggesting FGF21 may mediate maternal metabolic adaptation independently of thermogenesis.

Why this might work

During pregnancy, extra thyroid hormone tells the liver to make more FGF21 by turning off a signal that normally blocks FGF21 production. At the same time, the body stops fat tissue from making heat, so the extra FGF21 is used to move energy around the body for the growing baby instead of burning it as heat.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Pregnancy negates thyroid hormone-induced pyrexia.

    When pregnant mice get extra thyroid hormone, their bodies make more FGF21—a hormone that helps use energy—but their fat doesn’t get hotter. This suggests FGF21 helps the mom’s body use energy in a different way, not by making heat.

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

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