Why Bryan Johnson Quit Rapamycin
Bryan Johnson took rapamycin for almost five years chasing its longevity promise, then stopped on September 28, 2024. The first year-long randomized trial of rapamycin for healthy aging (PEARL) missed its primary goal of reducing visceral fat, though it modestly improved lean mass, pain and self-reported wellbeing in some participants. Johnson's own stated reason for quitting was that side effects he was tracking, including skin infections and metabolic changes, no longer felt worth it for unproven benefit.
Understand the study design Healthy older adults randomized to placebo, 5mg/week, or 10mg/week rapamycin for 48 weeks
This is the first completed long-term randomized controlled trial of rapamycin for longevity in healthy humans, so its result matters more than anecdote.
See what the trial showed Missed its primary visceral-fat-reduction endpoint; improved lean tissue mass and pain in women on 10mg/week, improved self-reported wellbeing on 5mg/week, no significant difference in adverse events over one year
A trial missing its primary endpoint is the honest headline, even though some secondary measures moved in a favorable direction.
See his stated reasoning Stopped September 28, 2024 after nearly 5 years of use, citing side effects he tracked himself: intermittent skin/soft-tissue infections, lipid abnormalities, elevated glucose, and a higher resting heart rate
His own account is a single self-report (n=1), not controlled evidence, but it's a real, first-person data point from the most measured rapamycin user in public life.
Understand what rapamycin actually is A prescription immunosuppressant, originally for organ-transplant patients; off-label longevity use in healthy people is not FDA-approved and rests on one 48-week RCT plus animal and cell data
This is not a supplement decision; it carries real prescription-drug risk and requires a physician.
Rapamycin is a prescription immunosuppressant, originally used to prevent organ-transplant rejection, that gained a longevity following on the strength of animal-lifespan data and small human trials.
View sources
I Stopped Taking Rapamycin (Bryan Johnson, official blog)
PEARL Trial: Rapamycin in Generally Healthy Older Adults (PMC, 2025)
Not medical advice. This page is for education only and is not a substitute for professional medical care. Consult a qualified clinician before changing your health routine.
Editorial disclosure. This protocol is written and fact-checked by the YourProtocol editorial team directly from the primary sources cited below; it is not written or reviewed by any outside expert.
Is this for you
- Anyone curious why Bryan Johnson stopped taking rapamycin
- Longevity enthusiasts considering off-label rapamycin
- Anyone repeating rapamycin hype without knowing the trial evidence
- Readers who want the honest evidence picture, not the hype
Cautions
- Rapamycin is a prescription immunosuppressant; off-label use for aging is not FDA-approved and carries real infection and metabolic risk
- This is based on one 48-week randomized trial; long-term safety and benefit in generally healthy people remain unknown
- Johnson's personal experience is a single self-report (n=1), not controlled evidence
- Educational only, not medical advice; never start or stop a prescription medication without a physician