Every once in a while on a trip to the library my housemate hands me a book. They are never something I'd have selected for myself, but I pretty much always check them out, and usually appreciate them. This is one of those books.

I gave it four stars, but realistically speaking it had 3 major sections: one good but flawed, one excellent, and one trite, hackneyed, and probably wrong. It also has an IMO insane wish-fulfillment premise.

The purpose of this book is to popularize the idea that if humanity put more effort and money into research, many people now young adults might survive indefinitely, in reasonable health, with no more chance of dying in their 100th or 200th year than in their 20th.

IMNSHO this is crackpot territory, or at least extreme wishful thinking. I've known a lot of people with this belief, and I suspect the belief is primarily the result of fear of aging and death, and is usually seen among "spoiled brats" - i.e. people who've been near the top of the human status hierarchy in many parts of their lives. It's particularly common among tech billionaires, along with two other implausible beliefs - the idea that if their corpse is flash frozen, they'll eventually be restored to life, and the idea that their "self" can be uploaded to the Cloud, granting them conscious immortality there.

So why do I like this book? Because the middle section is the best discussion of aging and related research, intelligible to laypeople, that I have ever seen. It has footnotes that include links to much of the source material, on a web site lovingly maintained by the author. It's full of optimism, but not to the point of idiocy - when an approach was tried and failed, it says so. And when some approach has only been tried in mice - or worse, in earthworms - it makes clear that this only means that it might be worth a try, not that we should expect it to work in humans. And this section is more than half the book.

Every once in a while, it becomes screamingly obvious that the author is a science writer, not a scientist. He makes fewer errors than most science writers - a breed I generally avoid - but he's made a few that stick out like the proverbial sore thumb. (OTOH, I've seen worse in medical journals, though not often.)

This book starts with a discussion of why living beings age - i.e. their health degrades as they get older - how much it varies between species, and evolutionary models for why all these different pattens might evolve. Good discussion, but he never mentions menopause, which invalidates some theories of aging just by existing. (These would be theories he described as having been generally rejected - but it's still weird not to have menopause mentioned.)

The middle part is all kinds of detail about various aspects of aging, and the research on them, including attempts to find ways of slowing or reversing them. This section is great (see above), though my knowledge isn't deep enough to know what ideas and data he failed to include, and whether that matters. This section rates 4 1/2 or even 5.

The last two sections are, IMO, made of fail. One talks about how we could all live forever if we put enough money into research. In the course of this he falls headlong into a stupid but common fallacy. If you find a measure that correlates with longevity - some kind of indicator of life expectancy more accurate than chronological age - there's no longer any need to wait the decades for realistic human trials - just look at changes of this measure before and after some intervention. Because of course the measure will continue to be accurate when clever people start working hard to improve the measure, without looking to see if it still reliably measures their actual goal. Managers commit this fallacy daily - and find that their staff can and do teach to the test (metaphorically speaking); they get lots and lots of a behaviour that used to go along with what they really want (but can't easily measure), and no more of what they wanted.

The other gives advice about how to increase your odds of being one of those who lives long enough to receive the new treatments. That's the same old, same old advice everyone gives, plus a few things outside of anyone's control. (e.g. "be female"). The one thing he may be doing right here is downplaying supplements. In the middle section he refers to a meta-study that basically concludes that statistically speaking most supplements have no net effect on life expectancy, with a handful having a negative effect. (Don't take vitamin A; taking the vitamin A precursor beta-carotene may also have a negative effect, but if so it's much smaller. Vitamin E also may have a net negative effect.)

Finally, I note that he seems to see his old people, pre-indefinitely-postponed frailty, having the same lifestyles as young adults. Of course he's forgotten menopause again; if that's partly governed by a limited supply of ova, it will be even less possible for women to delay child-bearing to the point where they are advanced enough in their careers to afford full time care, etc.

At any rate, the combination of the two big goofs and the implausible premise leaves me unconvinced by his arguments about how easy this could be. Read this book with cynic-glasses, not rose-tinted ones. (Be warned he's a quite persuasive writer.) But the book is still a great source of information, all in one place, and easily intelligible to lay people. Recommended. ( )

A good read if you want an overview of the fast-developing science of aging as it now stands. There's a lot of detail, somewhat too much for me, but it's up-to-date and clear. If you're looking for advice, it's pretty straightforward and not very exciting. Eat a balanced diet, exercise, sleep 7-8 hours a night, don't smoke, use sunscreen... ( )