Why more thyroid hormone doesn't always help you lose weight

Original Title

Thyroid Function Variation in the Normal Range, Energy Expenditure, and Body Composition in L-T4–Treated Subjects

Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms

Summary

Even when thyroid hormone levels are normal, some people on thyroid medicine have more of one hormone (fT3) — and that’s linked to both burning more calories and having more body fat.

Proposed Mechanism
fT3-mediated increase in resting energy expenditure
Supported by evidence
fT3-mediated increase in carbohydrate oxidation
Supported by evidence
fT3-mediated increase in physical activity energy expenditure (light intensity)
Supported by evidence
adiposity-driven fT3 generation via bile acid and insulin signaling
Suggested

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Quality Analysis
Methodology
58%
Moderate QualityOverall Score
Cross-Sectional StudyMedicine

Systematic Reviews & Meta-Analyses

Max 100

Randomized Controlled Trials

Max 90

Cohort Studies

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Case-Control Studies

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Cross-Sectional Studies

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Case Reports & Case Series

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Expert Opinion & Narrative Reviews

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StrongerWeaker
Cross-Sectional Studies
Level 3b
58

58 / 44

Evidence Score

A snapshot of a population at a single point in time. Can identify correlations and prevalence, but cannot determine the direction of cause and effect.

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