As percentages of elderly people rise in many societies, age‐related diseases have become more prevalent than ever. Research interests have been shifting to delaying age‐related diseases by delaying or reversing aging itself. We use metformin as an entry point to talk about the important molecular and genetic longevity‐regulating mechanisms that have been extensively studied with it. Then we review a number of observational studies, animal studies, and clinical trials to reflect the clinical potentials of the mechanisms in lifespan extension, cardiovascular diseases, tumors, and neurodegeneration. Finally, we highlight remaining concerns that are related to metformin and future anti‐aging research.

As percentages of elderly people rise in many societies, age-related diseases have become more prevalent. Research interests have been shifting to delaying age-related disease by delaying or reversing aging itself. We use metformin and rapamycin, two drugs at the center of anti-aging drug research, as an entry point to talk about important molecular and genetic anti-aging mechanisms that have been extensively studied with them, such as mTOR, AMPK, and epigenetic modifications. We also present a number of observational studies, animal studies, and clinical trials to reflect the potential and actual effects of the mechanisms. At the end, we list remaining concerns that not only apply to researches around metformin and rapamycin but also future researches to explore other anti-aging pathways and therapeutics.