Compare
Side by side.
| Testosterone replacement therapy | Metformin | |
|---|---|---|
| Evidence | GRADE B | GRADE B |
| Category | hormone | metabolic |
| Status | Rx | Rx |
| Typical cost | $100–$300 / mo | $5–$20 / mo |
| Mechanism | Restores testosterone to physiologic ranges, supporting libido, muscle, bone density, mood and red blood cell production. | Lowers glucose production by the liver and improves insulin sensitivity. It mildly affects mitochondrial energy signaling (AMPK), which may mimic some effects of caloric restriction. |
| Human evidence | Testosterone Trials (TTrials) showed improvements in sexual function, mood and bone density. TRAVERSE found no increase in major cardiac events vs placebo in at-risk men. Note: TRT can accelerate androgenetic hair loss via DHT. | Observational data suggest diabetics on metformin may have outcomes comparable to non-diabetics. The TAME trial is designed to test aging outcomes but has not reported. Some data suggest it can blunt exercise adaptations in older adults. |
| Side effects | Elevated hematocrit · Suppressed fertility · Acne, hair shedding (DHT) · Fluid retention | GI upset, diarrhea · Vitamin B12 deficiency with long use · Rare lactic acidosis (kidney impairment) |
Not medical advice — talk to a licensed clinician. Content is educational, reflects published literature, and is not a recommendation to start, stop or change any treatment.