Metformin is a prescription medicine used to lower blood glucose in type 2 diabetes. It is also studied for delaying diabetes in some people at high risk, but claims that it slows aging or extends life remain unproven.
Purpose, evidence and practical considerations.
The approved use is type 2 diabetes. Diabetes-prevention studies involved people at high risk of developing the condition; those findings do not establish an anti-aging benefit in otherwise healthy people.
Metformin has strong clinical evidence for blood glucose control in type 2 diabetes. In the Diabetes Prevention Program, it reduced progression to diabetes in a high-risk population, although intensive lifestyle change had a larger effect. Human studies have not established that metformin extends lifespan in people without diabetes.
Confidence: strong
Gastrointestinal effects are common, vitamin B12 can decline with long-term use and rare lactic acidosis is the boxed-warning risk, especially with severe kidney dysfunction, hypoxia or acute illness. Kidney function, contrast procedures, alcohol use and interacting conditions require clinician management. It is prescription-only and should not be started for longevity without a medical indication.
Metformin lowers hepatic glucose production and improves insulin sensitivity through several cellular pathways, including effects on mitochondrial energy state and AMP-activated signalling. Those established metabolic actions do not demonstrate slowed aging in people without diabetes.
Regulatory status: Metformin is a prescription medicine approved to improve blood glucose control in people with type 2 diabetes. It is not approved as a longevity or anti-aging treatment.
How people use it, with their schedules, context and original sources.
800-1,000 mg · Evening
Fasting mimetic — AMPK activation, metabolic support
500 mg · 6 weeks on, 6 weeks off
glucose control; AMPK activation
1 g/day · daily, with intermittent pauses
AMPK activation; to 'simulate a fast'
previously taken for longevity, not diabetes
Dose and schedule patterns reported in public protocols; these are observations, not prescribing advice. Private and hidden usage is excluded.
These share a protocol with this intervention. This does not establish that they work together or are suitable alternatives.