The Claim

In 6–8 week old piglets under fed conditions, peripheral conversion of thyroxine (T4) to triiodothyronine (T3) and reverse T3 (rT3) via extrathyroidal monodeiodination accounts for 70% of total T3 production and 92.8% of total rT3 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.

Quantitative
1 study reviewed
In plain English

In 6–8 week old piglets that have eaten, most of the active thyroid hormone T3 and nearly all of the inactive hormone rT3 are made outside the thyroid gland by converting T4 through a specific enzymatic process.

See the scientific wording

In 6–8 week old piglets, peripheral conversion of thyroxine (T4) to triiodothyronine (T3) and reverse T3 (rT3) accounts for the majority of total hormone production, with 70% of T3 and 92.8% of rT3 derived from extrathyroidal monodeiodination under fed conditions.

Why this might work

In young piglets, the thyroid gland releases thyroxine, but most of the active hormone (T3) and inactive hormone (rT3) are made by other tissues like the liver and muscle. These tissues use special enzymes to chop off one iodine atom from thyroxine: removing it from the outer ring makes T3, removing it from the inner ring makes rT3. Under normal feeding, the body produces far more rT3 than T3 this way, and almost all of the rT3 and most of the T3 come from this process, not from the thyroid.

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.

    In young piglets, most of the important thyroid hormones aren't made by the thyroid gland itself—they're made by other parts of the body that convert a main hormone (T4) into active (T3) and inactive (rT3) forms. The study proved this is true under normal feeding conditions.

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

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