Research

Hormonal

Within the normal physiological range, higher serum TSH concentrations are associated with greater body weight and increased longitudinal weight gain.

If you are gaining weight despite stable habits, check your TSH even if it falls within the 'normal' lab range. Higher TSH levels within this normal window are linked to higher body weight and weight gain, suggesting that optimizing thyroid function might be a relevant factor in weight management.

GoodSupportsHIGH confidence
Thyroid function (as assessed by serum TSH concentration) within the reference range is associated with body weight in both sexes. Our findings raise the possibility that modest increases in serum TSH concentrations within the reference (physiologic) range may be associated with weight gain.
Caroline S. Fox · Archives of Internal Medicine · 2008

Why this rating

Large community-based cohort (n=2407), rigorous statistical adjustment, but observational design limits causal inference.

Source

Relations of Thyroid Function to Body Weight<subtitle>Cross-sectional and Longitudinal Observations in a Community-Based Sample</subtitle>

Caroline S. Fox · Archives of Internal Medicine · 2008

DOI 10.1001/archinte.168.6.587

cohort · n=2407Cited 296×
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DOI resolved against Crossref · corpus check 2026-06-10

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