There is certainly good scientific evidence that certain actions will help an individual extend hir healthy functional years of life, particularly when all combined together in a complete and self-consistent regimen. In that section you contradicted yourself by stating the “exercise” and “not smoking” were such actions (even though Jeanne Calment smoked for most of her life and likely died earlier as a result of finally stopping smoking). And this has no relationship to maximum life extension which is a whole other story, although there is certainly good evidence that CR and/or IF together with eating highly healthy foods, sufficient muscle activity and perhaps a few evidentially based supplements will extend the average healthy lifespan of a group of humans, even if only a little since humans are naturally much longer lived animals than those for which this has been well shown.