The Claim

In 6–8 week old piglets, food restriction increases the proportion of triiodothyronine derived from peripheral conversion from 70% to 83% and decreases the proportion derived from thyroidal secretion from 30% to 17%, resulting in a relative increase in extrathyroidal contribution despite an overall reduction in total hormone production.

Source: Extrathyroidal conversion of thyroxine to 3,5,3'-triiodothyronine (T3) and 3,3',5'-triiodothyronine (rT3) and its contribution to total triiodothyronines production rates in fed and food restricted piglets.

What the research says

Supports is higher

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

Supports
8score
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 6–8 week old piglets, reducing food intake changes the source of triiodothyronine so that a larger percentage comes from conversion in peripheral tissues and a smaller percentage comes directly from the thyroid gland, even though the total amount of hormone produced decreases.

See the scientific wording

In 6–8 week old piglets, food restriction shifts the source of triiodothyronine production from 70% peripheral conversion to 83% peripheral conversion, and from 30% thyroidal secretion to 17% thyroidal secretion, indicating a relative increase in extrathyroidal contribution despite overall reduction in hormone production.

Why this might work

When food is restricted, the thyroid gland produces less of the hormone thyroxine, which causes the liver and muscles to change how they process it. Instead of converting most of it into the active hormone triiodothyronine, these tissues convert more of it into an inactive form. This reduces the total amount of active hormone in the body but increases the proportion that comes from outside the thyroid gland.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Extrathyroidal conversion of thyroxine to 3,5,3'-triiodothyronine (T3) and 3,3',5'-triiodothyronine (rT3) and its contribution to total triiodothyronines production rates in fed and food restricted piglets.

    When young pigs don’t eat, their thyroid makes less of a key hormone, but their body makes more of it in other tissues like muscles and liver — so even though there’s less hormone overall, a bigger share comes from outside the thyroid gland.

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

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