This is actually a book review of a book called Lifespan by a biologist named David Sinclair. The review is by Scott Alexander, which is why I saw it.
Scott starts his review this way:
David Sinclair – Harvard professor, celebrity biologist, and author of Lifespan – thinks solving aging will be easy. “Aging is going to be remarkably easy to tackle. Easier than cancer” are his exact words, which is maybe less encouraging than he thinks.
Which made me chuckle. I’d certainly like to believe that aging will turn out to be an easy problem to solve; ideally I’d like that to turn out to be true in, say, the next five years. Or, if aging turns out to be easy to roll back so that we can provide renewed youth to the old, then any time in the next thirty to forty years would probably do. Nevertheless, I’m having enough trouble right now that I’m all for solving the problem of aging right now, this minute, rather than waiting to see how decrepit I can possibly get in the next forty years.
However, I don’t mean to be cynical, but “celebrity biologist” is not the credential that makes me feel optimistic about this person’s judgment on this topic.
Okay, so, Sinclair is reaching for epigenetics to explain his cool ideas about how to beat aging. There’s a remarkable field! We know almost nothing about how epigenetics actually works, which again, isn’t to say that we haven’t learned a lot about it in the past 20 years. It’s just there’s so much more we don’t know. I do suspect that all sorts of people invoke epigenetics as a magic black box, which does make it handy as a potential solution for all kinds of things. Here’s how Sinclair invokes this black box:
So Sinclair thinks aging is epigenetic damage. As time goes on, cells lose or garble the epigenetic markers telling them what cells to be. Kidney cells go from definitely-kidney-cells to mostly kidney cells but also a little lung cell and maybe some heart cell in there too. It’s hard to run a kidney off of cells that aren’t entirely sure whether they’re supposed to be kidney cells or something else, and so your kidneys (and all your other organs) break down as you age. He doesn’t come out and say this is literally 100% of aging. But everyone else thinks aging is probably a combination of many complicated processes, and I think Sinclair thinks it’s mostly epigenetic damage and then a few other odds and ends that matter much less.
I will add here the observation that aging honestly does have to be something that can be basically turned off for some animals, because quite a lot of animals do not age in the way we do. Carp and turtles are perhaps not ideal models because they aren’t mammals, so I’ll just comment instead that bowhead whales definitely live a lot longer than we do, with reasonable estimates that they may live at least 200 years, probably substantially longer. So … I’m not saying it seems too unlikely that we might find a way to flip off aging. Maybe.
Ah, this is funny. Sinclair thinks deprivation is a fine idea for convincing your body that times are tough and it needs to hunker down and not age. He’s thinking of starvation, but other forms of deprivation as well. The idea that deprivation may improve things via epigenetics has been around for awhile, as I’ve seen arguments that obesity is substantially more likely for people whose grandparents never experienced a period of starvation. So there’s that. Scott quite reasonably poses this question:
Suppose you’re not a mouse, can’t get genetically engineered, and you have a normal aversion to diet and exercise. Is there a pill you can take?
And look, yes, there is! But it looks like Rapamycin has substantial side-effects. But there’s also this:
The other pill is nicotinamide riboside aka NR (and its close cousin nicotanimide mononucleotide aka NMN). The reactions catalyzed by sirtuins involve nicotinamides, and the more nicotinamides you have, the more effective sirtuins are. NR and NMN are cheap, simple chemicals you can buy at any supplement store for $20, and Sinclair is pretty convinced they’re a fountain of youth. He says that when his own father started becoming decrepit, he convinced him to take NMN, and over the space of a few months he started becoming energetic and spry again, and is now traveling the world despite being well into his 70s.
Hmm. Amazon suggests to me that $20 is a wild understatement of the cost. Though of course Scott doesn’t say $20 per what number of pills. But it looks like the cheapest Amazon offers is NR at $40 for a thirty day supply of pills. (And yes, that’s definitely the cheap version.)
This is Scott Alexander, so this is a very long book review. I’m going to now jump much closer to the end, which is where Sinclair says some stuff that … actually does seem pretty persuasive:
Sinclair thinks curing aging is easier than curing cancer. For one thing, aging might be just one thing, whereas cancer has lots of different types that need different strategies. For another, total cancer research spending approaches the hundreds of billions of dollars, whereas total anti-aging spending is maybe 0.1% of that. There’s a lot more low-hanging fruit!
But also, even if we succeed at curing cancer, it will barely matter on a population level. If we came up with a 100% perfect cure for cancer, average US life expectancy would increase two years – from 80 to 82. Add in a 100% perfect cure for heart disease, and you get 83. People mostly get these diseases when they are old, and old people are always going to die of something. Cure aging, and the whole concept of life expectancy goes out the window.
And then Scott comes out with many cogent arguments why curing aging would be a dandy thing to do if we could.
I feel that, given this is primarily a blog about SFF and writing, I would be remiss not to pull the subject in that direction. Fortunately, this is easy!
The Serrano Legacy books by Elizabeth Moon are space operas set at a time when longevity treatments are just beginning to have a big effect on society. Now, in my opinion, the first three books — Hunting Party, Sporting Chance, and Winning Colors — are the best books in the series, and the topic is just being developed in those. Nevertheless, this series is fundamentally concerned with the topic of longevity and the social consequences that sudden increases in longevity may cause.
Kim Stanley Robinson also does a lot with increasing longevity in the Mars trilogy. Remember the big deal with memory and longevity? And then people start living basically forever, so that only accidental death is a real thing. Huge effects on personal psychology and on society.
Heinlein did longevity a different way, via selective breeding, which almost certainly would fail, by the way. Humans do (far) too much breeding outside of marriage and, even worse, longevity is most likely really complicated genetically. That is, if you have someone whose family tends to be long-lived because they have genes that say “don’t get cancer,” and someone else whose family tends to be long-lived because they have genes that say “extended vigor,” those genes aren’t the same and you would most likely not reliably produce extended lifespans in offspring of those families. Unless you practiced extensive inbreeding with your tightly controlled slave population and then sure, but that is quite a different backstory.
I’m sure there are lots of others. If a particular title occurs to you, by all means drop it in the comments. Individual immortals are not what I’m thinking of here; only population- or society-wide changes.
Here’s a post that declares that as a rule, SF that handles this topic tends toward the dystopian end of the spectrum and that in general people tend to think that dramatic increases in longevity would be bad. I totally disagree, and that’s not just because I’m getting older. Scott Alexander frames my opinion perfectly, so I’ll end with another tidbit pulled out of his post:
And finally, what’s the worst that could happen? An overly literal friend has a habit of always answering that question with “everyone in the world dies horribly”. But in this case, that’s what happens if we don’t do it. Seems like we have nowhere to go but up!
6 thoughts on “Solving aging? Piece of Cake!”
I can think of just a few other things than epigenetic damage that qualify as aging. Most are pretty obvious.
Cory Doctorow’s first book, down and out in the magic kingdom, takes place in a post-aging, post-scarcity setting.
I’ve always been fascinated by the aging process. I remember for a while, everyone thought telomeres were the secret to eternal life. (Lobsters are immortal, after all, and their telomeres don’t shorten!). I actually did some research investigating if the enzyme that repairs telomeres varies by dog breeds, to try and figure out if that may be why little dogs generally live so much longer than big dogs (https://bmcvetres.biomedcentral.com/articles/10.1186/1746-6148-10-20). We didn’t find that to be the case, but we did find that the polymorphisms that exist in the gene likely predate development of current breeds, which is interesting.
If anti-aging science interests you, you might also check out the Methuselah Foundation. They fund some anti-aging projects and have interesting ideas on the causes of aging itself.
Regarding sci fi books, I really like the Scythe series by Neal Shusterman and how it deals with immortality and lack of disease in humanity. Shusterman really goes into some nitty-gritty details world building wise that I found very satisfying.
Thanks for the link, Camille! And the pointer to the Methuselah Foundation.
Right now I’m watching my oldest dog age suddenly and rapidly, very different from other old dogs I have had. I wish for all our sakes we could make that not happen!
I understand that for sure, and am so sorry to hear. I think every dog person would give their dogs an extended life if given the chance.
The usual “large dogs age faster*” makes sense up to a point. Wolves in captivity live up to 20 years, so one might expect dogs of similar size (70-110lbs) to do the same.
* wear and tear on body is too high.