The Claim

In elderly individuals with low selenium status, daily supplementation with 200 µg of selenium and 200 mg of coenzyme Q10 for four years significantly increases free triiodothyronine (fT3) levels and reduces free thyroxine (fT4) levels, suggesting enhanced conversion of T4 to T3 via increased deiodinase activity, which may improve metabolic and cardiovascular outcomes.

Source: Supplementation with selenium and coenzyme Q10 in an elderly Swedish population low in selenium — positive effects on thyroid hormones, cardiovascular mortality, and quality of life

What the research says

Supports is higher

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

Supports
81score
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.

Cause and effect
1 study reviewed
In plain English

In older adults with low selenium levels, taking 200 micrograms of selenium and 200 milligrams of coenzyme Q10 daily for four years is associated with an increase in free triiodothyronine and a decrease in free thyroxine, indicating a change in thyroid hormone conversion that may influence metabolic and cardiovascular health.

See the scientific wording

In elderly individuals with low selenium status, daily supplementation with 200 µg of selenium and 200 mg of coenzyme Q10 for four years significantly increases free triiodothyronine (fT3) levels and reduces free thyroxine (fT4) levels, suggesting enhanced conversion of T4 to T3 via increased deiodinase activity, which may improve metabolic and cardiovascular outcomes.

Why this might work

Selenium is used to make enzymes that convert the inactive thyroid hormone T4 into the active form T3 and into reverse T3. More of these enzymes become active when selenium levels rise, so more T4 is turned into T3 and reverse T3. This lowers the amount of T4 in the blood and raises T3, which tells the brain to reduce signals that stimulate thyroid hormone production.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Supplementation with selenium and coenzyme Q10 in an elderly Swedish population low in selenium — positive effects on thyroid hormones, cardiovascular mortality, and quality of life

    In older people with low selenium, taking selenium and CoQ10 daily for four years helped their bodies turn more of the inactive thyroid hormone (T4) into the active one (T3), which may help their metabolism and heart health.

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

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