Research

Hormonal

Testosterone replacement therapy in older men with confirmed late-onset hypogonadism improves body composition by decreasing fat mass and increasing lean body mass.

If you are an older man with symptoms of low testosterone (like low libido, fatigue, or loss of muscle mass) and your blood tests confirm low levels, testosterone therapy can help you lose fat and gain muscle. It is not a magic bullet, and you must be monitored for prostate health and blood counts. If you don't feel better after a few months, the treatment likely isn't working for you.

LimitedSupportsHIGH confidence
In men with hypogonadal values of testosterone, testosterone administration improves body composition (decrease of fat mass, increase of lean body mass; level 1b, grade A; Snyder et al, 1999b; Liverman and Blazer, 2004; Isidori et al, 2005b; Page et al, 2005; Allan et al, 2008).
C. Wang et al. · Journal of Andrology · 2008

Why this rating

Rated Level 1b, Grade A based on randomized trials and meta-analyses cited.

Source

Investigation, Treatment, and Monitoring of Late‐Onset Hypogonadism in Males: ISA, ISSAM, EAU, EAA, and ASA Recommendations

C. Wang et al. · Journal of Andrology · 2008

DOI 10.2164/jandrol.108.006486

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DOI resolved against Crossref · corpus check 2026-06-10

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