All fair points! That said, I think extended lifespan is a very reasonable thing to expect, since IIRC from longevity research that caloric restriction extends lifespan (from animal studies); this seems like a very natural extrapolation from that.
I think metformin was supposed to have effects similar to caloric restriction, and does appear to reduce all-cause mortality, even though most users are diabetic.
All fair points! That said, I think extended lifespan is a very reasonable thing to expect, since IIRC from longevity research that caloric restriction extends lifespan (from animal studies); this seems like a very natural extrapolation from that.
I think metformin was supposed to have effects similar to caloric restriction, and does appear to reduce all-cause mortality, even though most users are diabetic.