Ageing
Both descriptive and prescriptive; vitalism, lifespan, healthspan
2022-01-11 — 2026-02-11
Wherein longevity schemes are surveyed, quackery is cautioned against, and blood plasma dilution with saline and albumin is noted as rival to young-blood tales, with biomarkers left pending.
General theory of ageing and how we might avoid it. Placeholder.
See also biomarkers.
Lifespan, healthspan, and ageing aren’t my area of research. I’m not qualified to assess, in specific detail, the outlandish claims made by snake-oil sellers, because I don’t know biology well enough. I haven’t put a proper literature review high enough on my to-do list. That said, I can assess crap statistics and bad reasoning well enough to report that wading through it can be tedious.
There is a danger of pseudoscience and quackery in this area, so beware. The incentives are clearly not great: since cashed-up older people rarely want to die, selling them small trials with marginal benefits and low reproducibility is a lucrative enough business to prop up a lot of bad science indefinitely.
Which interventions help us live healthier, longer?
Quantified self/nutrition etc. for lifespan extension. Probably best read alongside biomarker tracking.
1 Sirtuin stuff
As mentioned in Sinclair (2021), where he recommends taking various supplements that affect the sirtuin pathway, whatever that is.
Berberine, resveratrol, metformin, NAD+ precursors, fasting, etc.
See also
More metformin stuff:
- Does Metformin Work as an Anti-Ageing Drug?
- (Campbell et al. 2017; Kulkarni et al. 2018; Kulkarni, Gubbi, and Barzilai 2020; Mohammed et al. 2021)
I’m interested in reports that fasting also benefits the immune system. Fasting seems to work in mice (Brandhorst et al. 2024).
2 GlyNAC
This also keeps coming up in the podcast-sphere.
“Supplementing Glycine and N-Acetylcysteine (GlyNAC) in Older Adults Improves Glutathione Deficiency, Oxidative Stress, Mitochondrial Dysfunction, Inflammation, Physical Function, and Aging Hallmarks: A Randomized Clinical Trial” (Kumar et al. 2023)
3 Blood plasma dilution
Blood boys, etc.
Do we even need blood boys?
See this Open Philanthropy summary:
The challenge: Given the central role ageing plays in disease progression, a better understanding of the ageing process could lead to improvements in a broad range of health outcomes.
The research: Dr. Irina Conboy, a professor in the Department of Bioengineering at UC Berkeley, has made significant strides in the scientific understanding of how blood factors—hormones, proteins, and other molecules circulating in the bloodstream—influence ageing. Though Dr. Conboy’s work had already gained recognition by the time of our first grant in 2017, we believed it was still neglected relative to its potential in a field that had received much private investment but little public research funding.
With support from our team and other funders, Dr. Conboy:
- Developed micro-apheresis for mice, an innovative technique that allows filtration of blood to remove small molecules.
- Identified 10 novel biomarkers of ageing.
- Uncovered a major mechanism for rejuvenation through modulation of the TLR4 receptor, which appears to play a key role in age-related inflammation.
- Revealed (Kim et al. 2022) that diluting old blood (with saline and purified albumin (Yilmaz et al. 2011)) — rather than adding young blood, which has garnered provocative headlines—can have rejuvenating effects on muscle, liver, and brain tissue.
The impact: Dr. Conboy’s research offers a new perspective on how factors in blood affect ageing. Her findings suggest that identifying and counteracting pro-ageing factors in blood could potentially slow or reverse certain effects of ageing, opening new avenues for improving human health and longevity.
4 What biomarkers are cheap to track to assess the effectiveness of ageing interventions?
TODO
5 Collagen
Why would collagen supplementation (some sources recommend a protocol with vitamin C and exercise) help with collagen production? It all gets digested anyway, right? Some small studies suggest that eating collagen can still help collagen production (Czajka et al. 2018; DePhillipo et al. 2018; Shaw et al. 2017). I’d like a meta-analysis and some extra data.
6 Alternatives
7 Incoming
John Wentworth, Gears of Aging
Regional diversity in longevity trends in Western Europe / interactive map visualization
The Human Lifespan Probably has an Upper Limit … and Why That’s Good
[…] we can imagine a future in which we slow aging; but today, there’s no sign of such an elixir. And so we are faced with a simple mathematical problem; as long as aging remains inexorable, there is likely a natural upper limit to the human lifespan.
And that’s probably a good thing. You see, if the elixir of life were actually discovered, the risk is that the spoils of longevity would be hoarded by the rich. Thankfully, the opposite is true today. Indeed, one of the most stunning features of longer life expectancy is that it makes the human lifespan more equal.
The Old, Old, Very Old Man: Thomas Parr and the Longevity Trade
As the story goes, Old Tom Parr was relatively healthy for being 152 until a visit to noxious, polluted London in 1635 cut his long life short. Katherine Harvey investigates the early modern claims surrounding this supercentarian and the fraudulent longevity business that became his namesake in the 19th century.
Watch Don’t Die: The Man Who Wants to Live Forever about Bryan Johnson.
A review of Eric Topol’s Super Agers:
The book is broad and shallow, as if he’s trying to show off how many topics he’s familiar with. Too much of the book consists of long lists of research that Topol finds interesting, but for which I see little connection with aging. He usually doesn’t say enough about the research for me to figure out why I should consider it promising.
He mostly seems to be saying that the number of new research ideas ought to impress us. I care more about the quality of the most promising research than about the quantity of research.
The book is mostly correct and up-to-date, but I’m unclear what kind of reader would get much out of it.