I'm sorry, but this has been discussed extensively before. Michael Rae did some good analysis on the merits of Metformin. You can read it up here:
https://www.longecit...-mean-lifespan/
http://www.longecity...d-nondiabetics/
In short:
1. mice-studies show mixed results. Some studies show no statistically significant effect on lifespan (notably the best effects are seen on mice models of obesity; the neutral results occured in non-obese mice).
2. Studies comparing the disease outcome of diabetic metformin users to non-diabetic people are few and far between (most studies used in the review, that OP cites, did NOT do that!).
There was one famous epidemiological study in 2014, which claimed, that diaebtic metformin users perform better than non-diabetics. This study turned out to be seriously flawed because of monitoring and censoring problems:
- diabetics got frequent medical check-ups, thus any kind of disease was caught early on and treated (even those unrelated to diabetes); the non-diabetic controls got far less frequent medical check-ups
- if diabetic patients had a progression in their diabetic status, and had to take an additional drug (so in addition to metformin), they were excluded from the study from that point on. In other words: only the best performing metformin-users were used for the statistical analysis (and those, whose disease progressed - i.e. higher mortality - were left out)
Similar, in a current meta-analysis, that actually looked at NON-DIABETIC PEOPLE USING METFORMIN:
"Effect of metformin on all-cause and cardiovascular mortality in patients with coronary artery diseases: a systematic review and an updated meta-analysis." (July 2019)
https://cardiab.biom...2933-019-0900-7
Metformin only improved mortality for diabetic-people. But it did nothing for people without well established metabolic disease (as in the mice studies).
If you're a sedentary and heavily overweigth or sugar-consuming type of person, Metformin might be a good idea. If you don't got metabolic disease, you only get the side effects.
Edit:
here you can read up about some of the rodent studies in metformin and lifespan (they are even missing 2 of the neutral studies done by NIA):
https://www.ncbi.nlm...les/PMC3906334/
it's a very mixed situation between life-extension, neutral (= no effect), and shortening the life span (yes, that happened more than once).
Edited by Guest, 22 September 2019 - 02:43 PM.