The Claim

Ten days of total energy deprivation in healthy, normal-weight males is associated with a slight and late decrease in thyroxine (T4) levels and a minute reduction in thyrotropin (TSH) levels, indicating downregulation of the hypothalamic-pituitary-thyroid axis during prolonged fasting.

Source: Effects of total energy withdrawal (fasting) on thelevels of growth hormone, thyrotropin, cortisol, adrenaline, noradrenaline, T4, T3, and rT3 in healthy males.

What the research says

Supports is higher

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

Supports
21score
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.

Correlation
1 study reviewed
In plain English

In healthy, normal-weight men, ten days of complete fasting leads to a small reduction in thyroid hormone levels and a minor decrease in the hormone that stimulates the thyroid, reflecting reduced activity in the hormonal system that regulates metabolism.

See the scientific wording

Ten days of total energy deprivation in healthy, normal-weight males is associated with a slight and late decrease in thyroxine (T4) levels and a minute reduction in thyrotropin (TSH) levels, suggesting a downregulation of the hypothalamic-pituitary-thyroid axis during prolonged fasting.

Why this might work

When the body runs low on energy, it reduces signals from the brain that tell the thyroid to produce hormones, which lowers the production of active thyroid hormone and shifts metabolism to burn fat instead of using sugar, saving energy for the brain and heart.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Effects of total energy withdrawal (fasting) on thelevels of growth hormone, thyrotropin, cortisol, adrenaline, noradrenaline, T4, T3, and rT3 in healthy males.

    When healthy men fast for 10 days, their bodies slow down their thyroid system a little to save energy — this study shows their T4 and TSH hormone levels dropped slightly, just like the claim says.

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

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