Lifespan extension: separating fact from fiction
Thinking about longevity practically is a tricky affair. On the one hand, we have very little definitive knowledge about how to prolong your healthy years aside from the very obvious (exercise, don’t smoke, don’t be fat); on the other hand, by the time we have established that knowledge with much certainty, you may very well no longer be alive to take advantage of it. Coming up with actionable insights is therefore a complex exercise in scientific literacy and fuzzy evaluation of risk-reward tradeoffs. In this post, I would like to describe my own personal thought process and the conclusions to which I’ve come regarding my own “longevity stack.”
Estimated IQ distribution of children given IQ of parents
Let’s try to estimate the distribution of the “genetic IQ” of some offspring assuming that we know the parental “genetic IQ.”
High-quality studies on education, intelligence, and environmental effects
Heritability of intelligence Effect of gene-environment interactions on intelligence Effect of education on intelligence Assortative mating on intelligence Effect of famine on intelligence Effect of deafness on intelligence Effect of parental death on life outcomes Effect of education on life outcomes
Underrated aspects of the “genetic singularity”
We now know that human traits are largely:
- additively composed of thousands of non-pleiotropic genomic variants,
- largely independent without noticeable tradeoffs between different traits at the margin, and
- increasingly predictable from genetic data as models improve and biobanks get larger.
For simplicity I will define the “genetic singularity” as the point when people become freely able to explore the high-dimensional space of human genetic variation without restriction, easily selecting or editing embryos with +5 standard deviation boosts to tens or hundreds of desirable traits. In my view, this is inevitable and is perhaps 1-2 decades out.
Limited evidence for neurotoxic effects of popper usage
“Poppers,” or inhaled alkyl nitrites, constitute a class of quasi-legal recreational drugs used to enhance sexual experience primarily through their vasodilatory effects. Thus far, the risks of alkyl nitrite inhalation remain poorly understood among the population of recreational users. Two concerns about potential neurotoxicity are often raised: first, comparison to other classes of inhaled organic solvents, and second, reference to a murine study by Cha et al. in 2016. These concerns do not appear to be well-founded. However, isopropyl nitrites specifically, rather than isobutyl or amyl nitrites, are known to cause adverse ophthalmic reactions and may pose a general neurotoxic risk. If isopropyl nitrites are avoided and recreational use is sufficiently limited, overall neurotoxic risk appears low.
A practical, low-cost supplementation regime of vitamins C, B2, and E before recreational use of alkyl nitrates as partial prophylaxis against adverse effects
“Poppers,” or inhaled alkyl nitrites, are commonly used recreationally to enhance sexual experience. Usage of inhaled nitrites is associated with both acute and chronic toxicity, but understanding of practical risk management strategies remains poor.1 Here, we examine one of the primary adverse effects of inhaled nitrites, methemoglobinemia. Drawing from an extensive assortment of published data, we propose that recreational users of poppers take oral antioxidant supplements (3 g vitamin C, 400 mg vitamin B2, and 800 mg vitamin E) two hours before anticipated usage. This supplementation regime has the potential to modestly ameliorate short-term methemoglobinemia associated with inhalation of alkyl nitrites.