Acarbose — The Japanese Case
The underappreciated one
Acarbose blocks intestinal alpha-glucosidase, slowing carbohydrate digestion and blunting post-meal glucose spikes. It's widely used for diabetes in Japan + parts of Europe, barely used in the US. Its NIA ITP longevity result is one of the largest in the mouse literature — but it gets far less attention than rapamycin.
The NIA ITP result
The Interventions Testing Program's 2014 cohort showed acarbose extended median male-mouse lifespan by 22% and female by 5%. The sex-specific response is unusual. The mechanism involves both glucose blunting and altered gut microbiome — both plausible longevity levers in humans.
Side effects are the main barrier
Undigested carbs reach the colon, where gut bacteria ferment them. Result: gas, bloating, flatulence — usually self-limiting after 2–4 weeks but hard to tolerate for some people. Cardiovascular outcomes data in humans (STOP-NIDDM, ACE trial) show meaningful prevention of diabetes onset and some CV benefit.
Match acarbose vs metformin
Drag each characteristic to the drug it best fits.
This step is interactive — open the Thier app to try it.
Practical dosing — start low, with worst meals only
Standard tolerability protocol: start at 25 mg with the highest-carb meal of the day for 1–2 weeks, then add a second meal, then optionally a third. Most people land at 25–50 mg with their largest carb meals (pizza, pasta, rice-heavy dinners) rather than every meal. Skip when fasting / very-low-carb — there's nothing to slow. Carry a pure-glucose source (not table sugar — acarbose blocks sucrose breakdown) for hypoglycaemia in case you stack with other glucose-lowering interventions.
Key Takeaway
Acarbose is cheap, locally-acting, and has arguably the most impressive mouse-longevity signal of any approved drug. The GI side effects are real but usually manageable. For people with elevated post-meal glucose spikes, it's a reasonable tool — start at 25 mg with the worst meal of the day, build tolerance, and skip on low-carb days.