The Claim
Individuals with morbid obesity (mean BMI 46 kg/m²) have circulating thyroid-stimulating hormone (TSH) levels that are 170% higher and free triiodothyronine (FT3) levels that are 36% higher than those in lean controls, independent of thyroid disease status.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
People with severe obesity have 170% higher thyroid-stimulating hormone and 36% higher free triiodothyronine in their blood compared to people with normal weight, regardless of whether they have thyroid disease.
See the scientific wording
Circulating levels of thyroid-stimulating hormone (TSH) and free triiodothyronine (FT3) are 170% and 36% higher, respectively, in individuals with morbid obesity (mean BMI 46 kg/m²) compared to lean controls, independent of thyroid disease status, suggesting a link between adiposity and altered thyroid hormone metabolism.
Excess fat tissue reduces the number of thyroid hormone receptors in fat cells, so the body cannot detect how much thyroid hormone is circulating. This tricks the brain into thinking there is not enough thyroid hormone, so it keeps producing more of the signal that tells the thyroid to make more hormone, leading to higher levels of both the signal and the hormone in the blood.
What the research says
1 studyPeople with severe obesity were found to have much higher levels of two thyroid hormones in their blood than people with normal weight—even when their thyroid gland is healthy. This suggests that being very overweight changes how the body handles these hormones.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.