There are populations that consistently outlive and the only other thing I would add is stress removal in the form of relatively simple life styles.
And I mean here both sacrifice the things you hold dear directly, or indirectly - which for us here is predominantly our careers and places of living.
Exaggerating a little bit to underscore the point: I could likely add years to my QALY lifespan if I moved to countryside, picked up more manual labor that required me to move my whole body, and went hiking in between going to the gym -- but, the things I value are found in cities, the work I like is white-collar, I hate hiking, and I also have people I love to support and lifespan-friendly labor generally doesn't pay enough.
To live a life that's even remotely healthy we have to dedicate a significant amount of the precious spare time we have just to undo some of that damage.
I do not believe we are predisposed to adopt sedentary lifestyles. As kids most of us are very active, but we are taught to be sedentary. Both academically and professionally we are most rewarded for sedentary activities: doing extra coursework, building your resume. Is it any surprise we develop a sedentary lifestyle when such a lifestyle is most rewarded?
> If you want to live forever don't do any of the things that would make it worthwhile.
(Oh, and walking covered in sunscreen all the time - except not, because that's technology and chemicals; though surely there's some perfectly natural, organic, non-GMO ointment known from ancient times that works even better...)
That's how the other extreme looks like - but unlike the "bad habits" extreme, this one is actually what's needed to make a noticeable improvement your QALY lifespan. It's also a kind of life I wouldn't personally find rewarding - hence the question, what's the point of living longer if you have to live like this[0]?
Between this and the fact that approximately no one can afford living like that today, I say the whole idea of living longer by "just" living healthier is a lie.
--
[0] - This lifestyle is basically the Edo people[1] from the infamous Star Trek: TNG episode "Justice"[2]. Chilling out in a paradise, keeping fit bodies, and basically running around all day in between of making art and having sex with others, sure sounds like an alluring lifestyle to us (and to the protagonists on the show). Still, this episode lets the viewer ask themselves - would they rather be with the Edo, or on the Enterprise? I'd take the latter, thank you - pretty sure I'd go bored shitless after a year in that place. And while United Federation of Planets isn't an available option, even the regular life in the real world seems much more interesting and rewarding to me, if you look past the immediate appeal[3].
[1] - https://memory-alpha.fandom.com/wiki/Edo
[2] - https://memory-alpha.fandom.com/wiki/Justice_(episode)
[3] - See also: heaven in Christianity, which if you think more about it, is basically a place of infinite boredom - but it does look alluring to sustenance farmers of the middle ages, as it offered reprieve from the endless toil and oppressive lords.
You can very well argue that a typical 40h work week leaves too little time to do enough of the good things. But most people would still most likely keep kicking back and using their time inefficiently even if we had to work much less than now.
Remaining too much time sitting in static positions is bad, sure. But people doing physical work are also exposed to massive health risks as usually the load is repetitive and uneven. Both populations need corrective action, but for the physical worker it is more tricky to add a workout routine because their bodies are already overtaxed.
Healthy food being bland and bad tasting is simply a sign of not being able to cook well. Learn stir frying and add some herbs, spices, and sauces. (Yes, sauces often contain sugar, but IMHO it's well worth giving up candy for better tasting real food!)
I hope you are aware that many societies displayed in Star Trek (and similar SF) are for storytelling purposes almost necessarily either oversimplified, have weird traits, or are caricatures reflecting something out-of-universe? For most of them we know very little about how daily life is actually like for a civilian. Of course it doesn't seem compelling to be part of any of these societies. And it is unconvincing to argue that a healthy lifestyle is necessarily one where we won't be able to have fun.
Anyway the point of that episode was to highlight the extreme cost of maintaining such a society, not the lifestyle itself. And of course it would be quite appealing to explore the universe in the comfort of a five star hotel, which living and working on the Enterprise-D surely must feel like.
These things are quite literally the leading causes of death and impairments in the west...
Are his therapies are over the top and lacking a bit of experimental rigor? Probably. Does he look healthy af? Definitely.
And to me he doesn't look healthy af. His skin is good, sure.
Check this thing out, just launched a couple days ago https://virtualcellchallenge.org/
I've been exploring the current status of atom-level simulation of biological systems and it seems to be an even greater challenge than I expected. Apparently even MD is not as useful as I assumed because it doesn't model some important mechanisms such as bond formation and breaking.
Or what happens when we stop them? Perpetual adolescence seems mainstream now. But it would be nice to know if some of these changes should be brought up as well as pushed back.
We don't - people inevitably age and die. All you can hope to do is postpone these shifts, and I suspect a large component in the timing is genetic, so there isn't a magical solution that will work for everybody just because it works for the guy posting about the one guaranteed solution for preventing ageing, because it's worked so far for him.