Research

Hormonal

Testosterone replacement therapy significantly decreases serum leptin levels in older hypogonadal men, suggesting a hormonal modulation of adiposity regulation.

Testosterone therapy in hypogonadal men has been shown to lower leptin levels, a hormone involved in regulating body fat and hunger. This suggests testosterone may help modulate body composition, although this study did not show significant changes in body fat percentage or BMI.

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Testosterone significantly decreased leptin levels (control, delta -0.8 +/- 0.7 ng/dL; testosterone, delta -2.0 +/- 0.9 ng/dL; P < 0.02).
Rahmawati Sih et al. · The Journal of Clinical Endocrinology & Metabolism · 1997

Why this rating

RCT design with clear statistical significance, though the clinical relevance of leptin reduction alone is less defined than strength gains.

Source

Testosterone Replacement in Older Hypogonadal Men: A 12-Month Randomized Controlled Trial

Rahmawati Sih et al. · The Journal of Clinical Endocrinology & Metabolism · 1997

DOI 10.1210/jcem.82.6.3988

rct · n=32Cited 895×
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DOI resolved against Crossref · corpus check 2026-06-10

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