The Claim

In elderly individuals with low selenium status, four years of supplementation with selenium and coenzyme Q10 results in a significantly smaller increase in thyroid-stimulating hormone (TSH) levels compared to placebo, and a lower proportion of individuals exceeding the clinical threshold for subclinical hypothyroidism.

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

Among older adults with low selenium levels, taking selenium and coenzyme Q10 supplements for four years leads to a smaller rise in thyroid-stimulating hormone levels and fewer people reaching the diagnostic threshold for subclinical hypothyroidism compared to those taking a placebo.

See the scientific wording

In elderly individuals with low selenium status, supplementation with selenium and coenzyme Q10 for four years reduces the progression of subclinical hypothyroidism, as evidenced by a significantly smaller increase in TSH levels compared to placebo, with the proportion of individuals exceeding the clinical threshold for subclinical hypothyroidism rising from 2.5% to 9.6% in placebo versus 1.9% to 3.4% in the intervention group.

Why this might work

Selenium helps activate enzymes that convert the main thyroid hormone into its active form and into inactive forms, which tells the brain to stop producing the signal that tells the thyroid to work harder. This keeps thyroid hormone levels stable and prevents the signal from rising too high.

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 keep their thyroid hormone levels more stable, preventing the usual rise in TSH that happens with age.

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

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