The surprising part is that neutering males after puberty showed the larger increase:
> However, mice that were neutered as adults gained the most. The procedure stretched their lives by about 33%, compared with 19% and 26% increases, respectively, for the animals fixed before or after puberty.
That trend goes opposite of what would be expected from a simple area under the curve model where presence of the testes correlated with reduced lifespan.
The link between male hormones and aging has always been interesting but I think there’s going to be a renewed interest as TRT clinics have become common and even men who aren’t hypogonadal can now be prescribed TRT after a short consult with a doctor from their local clinic who never turns anyone down.
Among the people I know who were more cavalier with TRT and keeping their testosterone levels at the top of the normal range for years, all of them have started talking about how it feels they’ve aged. Anecdotally, they look older than their age to me, but I didn’t realize how much testosterone was associated with accelerated aging until I looked at the research. I always thought the visual changes were a side effect of the associated hair growth changes, facial structure changes, and lifestyle factors that often come along with the people who use testosterone at levels above what’s needed to get toward the median of the range.
The numbers in this study preprint are close enough that I’d want to see more replication, but it would suggest that the relationship is more complicated than simply having androgens accelerate aging.
IMO, all the evidence for castration increasing lifespan is pretty strong evidence that all the "I'm going to live 200 years" bluster by a certain contingent of techbros is merely that. I've yet to hear about any of them becoming eunuchs.
If mice studies were analogous to humans, we would have cured numerous things by now. I'm all for taking correlation as worthy of follow up research, but I aint chopping off my balls based on it.
They note that castration is known to benefit longevity in a wide range of mammalian species. So I think there is a good chance there is something real here. Anyway the real prize is of course the castration mimetic drugs they hint at, that would give the benefits without having to actually remove the balls.
> However, mice that were neutered as adults gained the most. The procedure stretched their lives by about 33%, compared with 19% and 26% increases, respectively, for the animals fixed before or after puberty.
That trend goes opposite of what would be expected from a simple area under the curve model where presence of the testes correlated with reduced lifespan.
The link between male hormones and aging has always been interesting but I think there’s going to be a renewed interest as TRT clinics have become common and even men who aren’t hypogonadal can now be prescribed TRT after a short consult with a doctor from their local clinic who never turns anyone down.
Among the people I know who were more cavalier with TRT and keeping their testosterone levels at the top of the normal range for years, all of them have started talking about how it feels they’ve aged. Anecdotally, they look older than their age to me, but I didn’t realize how much testosterone was associated with accelerated aging until I looked at the research. I always thought the visual changes were a side effect of the associated hair growth changes, facial structure changes, and lifestyle factors that often come along with the people who use testosterone at levels above what’s needed to get toward the median of the range.
The numbers in this study preprint are close enough that I’d want to see more replication, but it would suggest that the relationship is more complicated than simply having androgens accelerate aging.
It reminds me of Larry Niven's Pak Protectors.