Castration extends life span, but in a surprising way, mouse study suggests
science.org
science.org
> 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.
"all of them have started talking about how it feels they’ve aged"
As anecdotes go, I've seen completely the opposite posted all over the internet. Guys that hop on TRT and say its the best they've felt since their 20s.
Read enough of those posts and it becomes a potentially dangerous thought pattern, that the reason you don't feel like you did in your 20s is solvable. Or maybe not? Therein resides the issue with anecdotes, they're just not reliable unfortunately.
This is called the "honeymoon period" and it's a well known thing in TRT forums: Most people feel amazing when they start, then that amazing feeling stabilizes out to something much less over months or years.
Disturbing a lot of biological systems works this way: There are a lot of drugs and medicines that make people feel amazing when they first start taking them, but after some time they stabilize out to something much less. This is true of everything from caffeine through benzos, opioids, and amphetamines.
That doesn't mean there isn't a therapeutic benefit, but many people are disappointed to learn that they're not going to spend the rest of their lives feeling as amazing as they did from those first weeks and months.
There are some secondary problems with TRT where long-term usage, especially when the dose isn't quite right (often higher than it should be as people chase those feelings) leads to secondary problems as other hormones are thrown off.
It's surprisingly common for people on TRT to end up with libido issues, for example. Complete opposite of what most people think. Your local broscience master will tell you it's a matter of using a few different additional hormone modulating drugs on top, but most of the time when I see people go this direction they end up with very unstable moods and may never find a solution other than tapering off.
Which leads to the other big problem with TRT: Taking testosterone causes the testicles to atrophy. It's a common joke about body builders, but it's a real thing that happens. A lot of people experiment with TRT for a few months or years and then decide it's not worth it any more, at which point they discover that they can't just quit taking it because they're physically dependent. There are some ways to try to restart the body's systems, but it doesn't work for every situation.
If I took aphetamines I would feel more energetic and capable than I would without in the short term. But long term it might not make me more energetic and capable overall due to the adverse effects.
I'm sure part of it is genuine bro-science dumbassery, though: over the years I have probably overheard a dozen gym conversations indicating that someone thinks TRT will reverse their balding or improve their hair. The truth is exactly the opposite -- male hormones tend to exacerbate male pattern balding, because of course they do. I think many people try to model the world by attaching a "good" or "bad" bit to everything and there are cases with steep tradeoffs where this goes very wrong. TRT is one of them, and once they've decided "TRT good" then "TRT fixes hair" and "TRT fixes aging" are compression artifacts.
I still suspect it's mostly astroturf.
I feel really bad for anyone who is being served false info about TRT fixing hair on their head. If there's one confirmed possible downside, from what I can tell, that is it (there may be many more).
I kid, but only slightly: bro-science does not come from researching things on google or anywhere else. In theory it comes from personal experience, in practice it is usually made up on the spot or reverse-engineered from desires or self-interest.
That's effectively what I mean by "Google" in the bro science context. Even there you'll be hard pressed to find anecdotes from TRT supporters who claim it improved their head hair growth. I find a lot that note it increases hair everywhere ELSE but not the head.
That situation changes as the body stabilizes, the testes atrophy, and the brain gets used to the new set point.
That's why the TRT forums and Reddits are filled with complaints about "my TRT stopped working" when the honeymoon period ends.
9.4 yrs > 7.9 yrs .. 40k dogs tested
both sexes. females 26% longer. Males 13%
https://news.uga.edu/uga-research-finds-sterilized-dogs-live... https://www.theatlantic.com/health/archive/2013/04/study-spa...
Their records should be a good reference point even though they might not be scientific observations.
Self-optimizing life extensionists: hold my beer.
(So this doesn't end up just another RTFA thread, an interesting factoid: the "bellwether" is the castrated -- and thus relatively docile -- sheep that wears a bell, helping track the flock.)
Testosterone plays a role in stimulating release of IGF-1.
That would make a good case for castration after kids. But it needs to be sold really really well
Probably the only thing preventing half this site from reaching for the scissors.
It reminds me of Larry Niven's Pak Protectors.