What I'm saying is that it doesn't reverse aging, it merely slows it down, and not by much.

I don't think anybody's claimed that it reverses ageing, and if they have I think they would have clarified that they did mean 'slows' the ageing process. And there's no doubt that caloric restriction and IF both slow ageing relative to a normal caloric intake. I don't have the paper on me atm, but IIRC it was 30% longer lifespan in mice. Now whether you want to say ageing is slowed or that lifespan is increased, and I'm not denying that there's a legitimate difference, but either way caloric restriction is completely legitimate for both, and to the extent you said it's useless, I don't think that's fair at all.

For anybody interested, the mTor pathway is really interesting in this regard, and in general the effects of AMPK on cellular metabolism. TLDR is that in the modern world most people never activate these pathways (since we're always in a fed state). Ostensibly there will be some breakthroughs when we finally learn why these starvation pathways are so beneficial. Inflammation seems a decent guess - eating increases it, and fasting decreases it, as a general rule.

Isn't slowing down aging the goal of "longevity"? The word implies extending life, not necessarily renewing it.

Slowing it down feels like a half-measure. Especially knowing that it's a malleable process that can be reversed.

are there other studies on animals / mice which have a larger sample size? the one linked in the post has a sample size of 106 which to an untrained eye seems small. https://static1.squarespace.com/static/5a2069c3ccc5c5325fd05...