When I read Gulliver’s Travels in college, there were many parts that stood out to me (not the least of which was finally understanding where the word “Lilliputian” came from). But the bit that has really stuck with me for mumblemumble years is the part about the struldbrugs living on the island of Luggnagg. The struldbrugs were the beings that were immortal but not eternally youthful, so they just got older and more feeble. It was definitely not portrayed as a desirable existence, with the physical and mental ravages of time mounting up and no expectation of the release of death from old age. We could also discuss Swift’s thoughts on why the struldbrugs had to consider one another legally dead at 80 years old to avoid the ruin of society by the hoarding of wealth and power by the aged, but that might be a different Substack post (though it might come up again before the end of this one).
Americans have an uneasy relationship with aging and death. We don’t like to talk about either one as a natural part of life’s course. We don’t like to think about aging and death as practical and real things in each of our lives. We treat aging like a disease – indeed, the NIH’s National Institute on Aging is funded at around $4.5B, whereas the National Institute for Child Health and Human Development is only funded at around $1.8B (and these figures are before proposed destructive budget cuts in the last 2 presidential budget proposals). Our rituals around death are pretty haphazard too, with communities of faith often offering more in terms of standard operating procedures for handling death than American culture itself can offer. In medical settings, there’s often an assumption that pretty much anything is fixable, thus making aging and death things to be fought to the absolute bitterest end. Perhaps it’s not surprising, then, that between one in five and one in three Americans will die in an intensive care unit, and somewhere between 10% and 25% of total healthcare spending is accounted for by people’s last year of life.
So if we explicitly or implicitly believe that aging is a disease to be cured and death is optional, it’s not difficult to understand the rapidly growing interest in longevity science. The interest in life extension and immortality is of course very old. The Philosopher’s Stone was first mentioned in alchemical writings around 300 AD and was believed to be the key ingredient in an elixir (sometimes called the Elixir of Life) that would bestow youthfulness and immortality. But interest in life extension research has skyrocketed in the last few decades. In 1970, there were less than 100 PubMed indexed publications matching the search term “longevity”; in 2025, there were 6,548, a 65-fold increase. For comparison, “cancer” has seen a 14-fold increase in publications over the same time period, and “heart disease” has seen a 7-fold increase. The concept of “healthspan” or “healthy longevity” has also increasingly entered discussions and the scientific literature, the idea being that we make sure that as we’re avoiding aging and death, we don’t commit ourselves to the same fate as Swift’s struldbrugs but instead stay healthy and vibrant longer than we do now.
In and of itself, research on extending lifespan and healthspan is great. Indeed, I’ve published research on lifespan and healthspan extension (https://www.aging-us.com/article/101011/text ), and it was one of the most interesting and fun projects of my lab research career! With an outstanding team led by a superb graduate student, we found that we could make nematode worms live longer and stay healthy longer (worm version of healthy… they moved more, pooped more, that kind of thing) if we dosed them with a compound that’s being trialed in humans right now for a different thing but is easy and safe to take by mouth. And the REALLY nifty part was that the compound did its thing almost entirely at the level of preserving protein functions in ways that made total biochemical sense and with minimal effects on gene expression. We actually learned that which incubator the worms were in had a bigger effect on gene expression than the treatment, which was a huge surprise and phenomenally cool!
Longevity research has so many of the features that made me fall in love with science in the first place. There’s a place for biochemistry, genetics and genomics, cell biology, physiology, pharmacology, systems biology, and all the other basic and translational -ologies, so teams are usually multidisciplinary. You always end up talking about energy metabolism, redox balance, mitochondria, metabolic signaling pathways, control of cellular differentiation, and lots of other really deep and deliciously complicated biology. A lot of the biology is pretty fundamental, and so there are side benefits for many disease states to understanding and being able to affect that fundamental biology. And, the ultimate goal of extending natural lifespan feels both really big and important and just possibly achievable.
HOOOOWWWWWWEVER…
Maybe you’ve noticed a lot of chatter about longevity and biohacking and peptide stuff and a whole bunch of other things like that, especially amongst tech bro culture? There’s been a fair bit of it. Literally two hours before I wrote this sentence, a lengthy piece on the topic of biohacking was published in the New York Times (https://www.nytimes.com/2026/03/31/dining/biohacking-diets.html ). You’ve perhaps heard of Bryan Johnson’s somewhat ridiculous-sounding claims as part of his anti-aging/money-making scheme “Project Blueprint” or the various regimens being used and hefty investments in age-defying research being made by the likes of Sam Altman, Peter Thiel, Jeff Bezos, and other people with lots of money and no medical or biology training whatsoever (https://www.businessinsider.com/tech-billionaires-trying-to-hack-longevity-and-live-forever-2025-9 ). The tenor of the lifespan and healthspan discussion seems to have shifted from one of exciting science to one that is uncomfortably like a crusade or a fetish.
I have a few problems with this approach, starting with the basis of how scientific research is done. Research answers a question. The experiments and data *must* allow for the possibility that the answer is “no”. In this case, it is assumed that natural lifespan can be extended substantially, or that aging can be reversed at the cellular level and that that’s a good thing to do, or that it’s possible to avoid the fate of the struldbrugs. But what if the answer to any of these is “no, that’s simply not possible”? If one is truly asking a question, a compelling “no” is a gift as it allows other more fruitful avenues of inquiry to be followed. You go where the science and the data take you. But if you’re on a crusade for the Holy Grail of Your 150th Birthday, you might not be doing science anymore.
Then there’s the issue of who gets to live to be ultra-mega-old and stay healthy. As currently discussed and practiced, the pursuit of extending healthy lifespan beyond natural limits seems to be something only for the wealthy and privileged. Even those who advocate for life extension solely or primarily through dietary means – specific nutritional regimens, intermittent fasting, caloric restriction, and others – are typically describing approaches that are not practical for people who do not already have significant resources to devote to health and wellness. Just following the Mediterranean diet, frequently recommended as one of the healthiest diet plans by professional medical organizations including the American Heart Association, is estimated to cost a family of 4 approximately $285 per week in groceries. This is in the “moderate” weekly food budget category (basically in the middle of a 5 category ranking) and does not take into account the availability of time and effort required to acquire groceries and prepare meals. The reality is that millions of Americans are already making choices between affording healthcare and affording other basic needs including food (https://news.gallup.com/poll/702596/one-third-americans-cut-back-cover-healthcare-expenses.aspx ). The current state of longevity science seems to be that it is practiced and funded by people who are already going to live longer and healthier because of their access to high quality food, high quality healthcare, cleaner and safer living environments. And there doesn’t seem to be a plan for including those who are already falling behind or struggling just to keep up.
And then there’s the issue of scientific rigor around existing data. Under U.S. laws like the Federal Food, Drug and Cosmetic Act and the Dietary Supplement Health and Education Act, it’s permitted to sell things like dietary supplements and allude to health benefits. It is not permitted to make specific claims about specific benefits for specific diseases without FDA review and approval, hence the boilerplate language you’ve seen on any bottle of dietary supplement: “This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.” But there is a very large gap between what is permissible and what is scientifically supported or justified. When it comes to life extension in humans, the state of clinical evidence is that there are some approaches and interventions that have shown biochemical or cellular or physiologic changes that *might* correlate with or lead to a longer healthy lifespan. But… and this is important… there’s no clinical evidence that these interventions will make anyone actually live longer or actually preserve youthfulness or healthspan in humans. And yes, of course those kinds of studies are really hard to do. Why do you think we studied worms??!! They live and die quick enough to study in a reasonable timeframe and for less than a gajillion dollars. Do I think our worm results are intriguing? Absolutely! Would I love to do a clinical trial examining lifespan and healthspan in humans that is based on our worm results? YES! Do I take any version of the compound we tested based on its lifespan and healthspan effects in worms? I do not.
The pursuit of a healthy lifespan that exceeds natural limits makes perfect sense to me as a scientific endeavor. There’s incredibly cool science to be done, and we’ll learn a ton that will benefit other areas of human health. AND WE JUST MIGHT SUCCEED! But the science has to be actual science, done with appropriate attention to scientific rigor and with the intent of answering research questions rather than arriving at specific predetermined answers. And, there are much bigger and more pressing health issues that, in my opinion, ought to take scientific, medical, ethical, and social priority. Imagine if the tech bros turned their interests and their resources toward making that Mediterranean diet financially and practically accessible everywhere in the U.S. Imagine if billionaires decided to focus on increasing access to those things that we have really solid evidence for improving health and for helping people live longer and better, instead of sleeping in cold vests and ordering magic fetish peptide cocktails for infusion and only farting at certain times of day (or whatever, I don’t know what all they’re into). They could *actually* achieve life extension, for everyone.
Or… maybe you and I aren’t supposed to live longer and healthier under the billionaires’ plan? Immortality for me but not for thee? But remember what Swift said: “Otherwise, as avarice is the necessary consequence of old age, those immortals would in time become proprietors of the whole nation, and engross the civil power, which, for want of abilities to manage, must end in the ruin of the public.”
