Compare
Side by side.
| Rapamycin | Metformin | |
|---|---|---|
| Evidence | GRADE C | GRADE B |
| Category | mTOR | metabolic |
| Status | Rx | Rx |
| Typical cost | $30–$150 / mo | $5–$20 / mo |
| Mechanism | Rapamycin inhibits mTOR, a cellular growth switch. Dialing mTOR down shifts cells from 'build' mode toward maintenance and recycling (autophagy) — a pattern associated with longer life in many species. | 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 | Robust lifespan extension in mice, including when started late in life (NIA Interventions Testing Program). In humans, small trials of rapalogs improved vaccine response in older adults. The PEARL trial reported tolerability of low-dose weekly use with modest signals. No human lifespan data exists. | 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 | Mouth ulcers (stomatitis) · Elevated lipids and glucose · Impaired wound healing · Possible infection risk | 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.