Okay, neat! I have an idea, and it might be kind of farfetched, or not amenable to the types of analyses you are best at doing, but I’ll share it anyways. Here goes.
Given that there is a tradeoff between health and reproduction, I wonder if you could increase the expected lifespan of a healthy human male by having him take anti-androgens on a regular basis.
We already know that male eunuchs who are humans live longer than intact male humans. I suspect that most guys wouldn’t be willing to become eunuchs even if they valued having a long lifespan very highly, but being able to increase one’s expected lifespan by decreasing one’s testosterone levels while still remaining intact might be something that a few males would consider, if such a therapy were proven to be effective.
Anyways, after taking 10 minutes to look around on Google Scholar, I wasn’t able to find any papers suggesting that taking anti-androgens would be an effective anti-aging measure, so maybe this would be a viable project for someone to work on.
As an aside, I don’t know which mechanisms cause castrated men to live longer, but this seems relevant to the question of why/how castrated men live longer.
Great idea! Here’s how I can convert your prospective experiment into retrospective ones:
Comparing hazard functions for individuals with diagnoses of infertility versus individuals who originally enter the clinic record system due to a routine checkup.
This is interesting, but a clear confound is that people who enter for infertility are likely to be more conscientious, which correlates with lifespan.
Whether male eunuchs actually live longer is controversial to say the least. Eg, the effect is not seen in dogs. In humans there are clear confounds.
Also, t levels don’t seem to clearly correlate with decreased or increased lifespans. And as your last link points out, lower levels of t (ie hypogonadism) are correlated with increased risk of CVD mortality.
Also, t levels don’t seem to clearly correlate with decreased or increased lifespans. And as your last link points out, lower levels of t (ie hypogonadism) are correlated with increased risk of CVD mortality.
Yes, you’re right about that. The paper says that:
“Our meta-analysis shows that patients with CVD have, on average, lower testosterone level than healthy controls.”
However, the paper also says that:
“Taken together, these results suggest that low testosterone may be considered as a marker of poor general health status, negatively affecting prognosis, rather than a specific CV risk factor (11, 84–86, 95). Low testosterone level has also been associated with an increased mortality in patients affected by non-CVD...”
In fact, since there is a tradeoff between health and reproductive ability, we might expect the development of health problems in previously healthy males to cause testosterone levels to drop, as a means of offsetting some of the negative effects of said health problem. This could account for why lower levels of testosterone are correlated with increased CVD mortality.
However,
Whether male eunuchs actually live longer is controversial to say the least.
In my view there is reasonable evidence for a trade-off between health and reproduction between species, but not within species. Am I wrong on this?
On eunuch lifespan, you are basically relying on three studies, each of which are historical, ie the Mental Health studies in the mid 20th century and the historical Korean eunuch study. I think there are big problems in interpreting these studies. For example, it’s not like the eunuch lifespans in either sample is as long as men in wealthy countries, which makes things like infections and generally risky behavior a much stronger candidate for the mechanism, which wouldn’t generalize to lifespan today. What am I wrong about here?
Let me be clear that I want you to be right. It suggests a clear mechanism to increasing lifespan in men. I just don’t think that there’s very strong evidence for it.
Okay, neat! I have an idea, and it might be kind of farfetched, or not amenable to the types of analyses you are best at doing, but I’ll share it anyways. Here goes.
Given that there is a tradeoff between health and reproduction, I wonder if you could increase the expected lifespan of a healthy human male by having him take anti-androgens on a regular basis.
We already know that male eunuchs who are humans live longer than intact male humans. I suspect that most guys wouldn’t be willing to become eunuchs even if they valued having a long lifespan very highly, but being able to increase one’s expected lifespan by decreasing one’s testosterone levels while still remaining intact might be something that a few males would consider, if such a therapy were proven to be effective.
Anyways, after taking 10 minutes to look around on Google Scholar, I wasn’t able to find any papers suggesting that taking anti-androgens would be an effective anti-aging measure, so maybe this would be a viable project for someone to work on.
As an aside, I don’t know which mechanisms cause castrated men to live longer, but this seems relevant to the question of why/how castrated men live longer.
Great idea! Here’s how I can convert your prospective experiment into retrospective ones:
Comparing hazard functions for individuals with diagnoses of infertility versus individuals who originally enter the clinic record system due to a routine checkup.
This is interesting, but a clear confound is that people who enter for infertility are likely to be more conscientious, which correlates with lifespan.
Whether male eunuchs actually live longer is controversial to say the least. Eg, the effect is not seen in dogs. In humans there are clear confounds.
Also, t levels don’t seem to clearly correlate with decreased or increased lifespans. And as your last link points out, lower levels of t (ie hypogonadism) are correlated with increased risk of CVD mortality.
Yes, you’re right about that. The paper says that:
However, the paper also says that:
In fact, since there is a tradeoff between health and reproductive ability, we might expect the development of health problems in previously healthy males to cause testosterone levels to drop, as a means of offsetting some of the negative effects of said health problem. This could account for why lower levels of testosterone are correlated with increased CVD mortality.
However,
is a statement which I emphatically disagree with.
In my view there is reasonable evidence for a trade-off between health and reproduction between species, but not within species. Am I wrong on this?
On eunuch lifespan, you are basically relying on three studies, each of which are historical, ie the Mental Health studies in the mid 20th century and the historical Korean eunuch study. I think there are big problems in interpreting these studies. For example, it’s not like the eunuch lifespans in either sample is as long as men in wealthy countries, which makes things like infections and generally risky behavior a much stronger candidate for the mechanism, which wouldn’t generalize to lifespan today. What am I wrong about here?
Again, why don’t we see the effect in dogs? http://www.straightdope.com/columns/read/3068/does-castration-longer-life
Let me be clear that I want you to be right. It suggests a clear mechanism to increasing lifespan in men. I just don’t think that there’s very strong evidence for it.