The Claim

Selenium supplementation at a dosage of 200 μg/day for 12 months significantly increases serum selenium levels in adults with autoimmune hypothyroidism who are receiving levothyroxine therapy, but this increase does not alter thyroid hormone conversion efficiency as measured by the free triiodothyronine–free thyroxine ratio.

Source: Selenium supplementation and placebo are equally effective in improving quality of life in patients with hypothyroidism

What the research says

Supports is higher

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

Supports
79score
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

Taking 200 micrograms of selenium daily for a year raises selenium levels in the blood of adults with autoimmune hypothyroidism who are on levothyroxine, but it does not change how efficiently the body converts thyroxine into triiodothyronine.

See the scientific wording

Selenium supplementation (200 μg/day for 12 months) significantly increases serum selenium levels in adults with autoimmune hypothyroidism on levothyroxine, but this increase does not alter thyroid hormone conversion efficiency as measured by the free triiodothyronine–free thyroxine ratio.

What the research says

1 study
  1. Study: Selenium supplementation and placebo are equally effective in improving quality of life in patients with hypothyroidism

    Taking selenium pills for a year didn't change how the body converts one thyroid hormone to another, even though it lowered some immune markers. So, selenium helps the immune system but doesn't make thyroid hormones work differently.

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

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