The Claim

The average production rate of reverse-T3 in humans is 34.3 micrograms per day in hypothyroid patients and 33.0 micrograms per day in healthy controls, indicating no significant difference in the rate of extrathyroidal reverse-T3 synthesis between these groups.

Source: Extrathyroidal conversion of thyroxine to 3,3',5'-triiodothyronine (reverse-T3) and to 3,5,3'-triiodothyronine (T3) in humans.

What the research says

Supports is higher

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

Supports
44score
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.

Description
1 study reviewed
In plain English

In people with hypothyroidism and in healthy individuals, the body produces reverse-T3 at nearly the same rate: about 34.3 micrograms per day and 33.0 micrograms per day, respectively.

See the scientific wording

The production rate of reverse-T3 in humans averages 34.3 microng/day in hypothyroid patients and 33.0 microng/day in healthy controls, indicating that thyroid hormone replacement does not significantly alter the rate of extrathyroidal rT3 synthesis.

Why this might work

The body converts the main thyroid hormone into reverse-T3 in tissues like the liver and muscles, using specific enzymes that remove one iodine atom from the inner part of the molecule; this happens at the same rate whether or not a person has an underactive thyroid and is taking replacement hormone, because the conversion depends on the amount of available thyroid hormone in the blood, not on whether it came from the thyroid gland or from a pill.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Extrathyroidal conversion of thyroxine to 3,3',5'-triiodothyronine (reverse-T3) and to 3,5,3'-triiodothyronine (T3) in humans.

    People with underactive thyroids who take hormone pills make reverse-T3 at almost the same rate as healthy people, meaning the pills don’t mess up the body’s natural way of making this hormone.

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

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.