Research

Hormonal

Thyroid hormones (T4, T3) and insulin concentrations within the normal euthyroid range do not correlate with resting metabolic rate or protein turnover in healthy young adults.

If your thyroid levels are normal, they are not the primary driver of your metabolic rate differences. Focus on body composition rather than trying to 'optimize' normal hormone levels for metabolic boost.

GoodRefutesHIGH confidence
Neither resting metabolic rate nor protein turnover was related to total or free concentrations of thyroxine or triiodothyronine, within the euthyroid range.
Stephen Welle et al. · American Journal of Physiology-Endocrinology and Metabolism · 1990

Why this rating

Clear negative correlation reported with statistical analysis.

Source

Relationship of resting metabolic rate to body composition and protein turnover

Stephen Welle et al. · American Journal of Physiology-Endocrinology and Metabolism · 1990

DOI 10.1152/ajpendo.1990.258.6.e990

cross_sectional · n=47Cited 184×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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