I've been struggling for some time with the issue of how to know what and whom to believe when it comes to lifestyle medicine (the effects of nutrition, supplements, exercise, etc. on health on longevity)... and it has occurred to me that I'm ignoring the elephant in the living room. As I understand it, the one non-obvious lifestyle change for which there appears to be good evidence of a very strong effect on longevity is caloric restriction.
When I first heard about CR over twenty years ago there were already decades of research demonstrating its apparently universal efficacy in extending the lives of mice and other short-lived creatures, and the case for CR has only gotten stronger since then as research has progressed to longer-lived creatures. It is arguably misguided to spend a lot of effort trying to figure out the right supplements to take (given the equivocal nature of much of the evidence) if you haven't yet made CR part of your lifestyle.
Longevity is not the only factor of interest.
There's CR and CR. A paleo lifestyle will greatly increase natural tolerance to fasting, leading to longer periods without meals, up to one day at times. Deliberate CR is something different.
CR doesn't show up among blue zones or the world's oldest people. Rather, the opposite - enjoyment of life.
I read a chimp study that showed CR chimps lived longer but had terrible quality of life compared to the fat happy sly contented ad libitum eaters. That suggests it's a tradeoff between living longer slowly an