Testosterone levels show steady decrease among young US men

I completely blame the food. Even eating absolute junk in Europe I noticed I lost 5 or 6 pounds over 2 weeks.

Here if I eat junk food for 3 days my weight jumps by 7 pounds. I am a bit dismayed with all the attempts to normalize obesity in the US. I was morbidly obese up until I got serious about my weight in my early 20s. You can read all the dating books you want, but getting in shape is the only thing that works. It's much easier to hop on Reddit and complain though.

I'm very optimistic I'll be able to move to a healthier country once I retire at 40 or so. Not exactly easy to stay in shape when this country tries to pump us all full of corn syrup

So, after correcting for BMI, physical activity, etc, there was still a very significant decline in testosterone between 1999-2000 and 2015-2016.

This is something I can anecdotally confirm: A few years ago my libido was low and I had borderline depression. After my lifts exceeded 100 kg (220 lb), there was a noticeable positive correlation between my libido and the deadlift days.

Our bodies need to move. Isn’t there strong evidence that we can’t even function properly without exercise? I mean, basic functions like regular waste disposal/cell regeneration. Circulation is insufficient without some added pressure and agitation. All kinds of stuff.

We are too fat and lazy, period.

It’s an “easy” fix, but it’s also really, really, really hard. Man. I used to run 50km per week, now I don’t even walk 5km. So much kid stuff, work stuff, house stuff.

Sexual behaviors can radically change testosterone as well.

> Lokeshwar noted that even men with a normal BMI (18.5-24.9) had declining total testosterone levels (P < .05) during the same time frames.

There are men who exercise and yet have low T.

In the abstract of your [3] we see a problem. Quote:

> If you have a low level of fitness you are likely to have a greater increase in testosterone response to exercise. As your body adjusts to the demands of exercise the testosterone response will decrease.

Basically you have to be unfit to get a T boost from lifting some weights. If you're already fit and adapted to exercise, more exercise won't fix the T problem.

Ive been around this discussion a lot and everyone seems to want to blame the whole phenomenon on some chemical or another, "xenoestrogens" are thrown around a lot. Yes, there are more unnatural chemical compounds entering our bodies than in the past (also important to examine) but addressing the terribly unhealthy lives most of us lead is obviously the first step.

> After controlling for confounders—including year of study, age, race, BMI, comorbidity status, alcohol and smoking use, and level of physical activity—total testosterone was lower among men in the later (2011-2016) versus earlier (1999-2000) cycles (P < 0.001)

But if you look at the study the effect persists after controlling for both BMI and exercise. There must be more to it.

- High yield, less nutritious crops - Climate change - less physical activity

https://www.politico.com/agenda/story/2017/09/13/food-nutrie...

But sugar, or more specifically insulin can reduce testosterone in the blood as well. Sugar will also make you put on weight more easily and body fat will also increase estrogen.

[0]: https://en.wikipedia.org/wiki/Motte-and-bailey_fallacy

It doesn't "===" violence but if you're intentionally using "==" for type coercion, it could be true.

How exactly do you propose that a change in socially acceptable behavior in the span of about 40 years had a tangible effect on hormone levels? It's not like someone can say "oh getting into fistfights isn't cool anymore, better reduce my testosterone levels". Maybe if we were talking about a timespan an order of magnitude or two longer then sexual selection (high testosterone and more violent men being less favored as mates) could come into play, but again for a time span of 40-50 years that's just not feasible. Also, socially acceptable or not, violent and aggressive men typically don't have problems finding sexual partners; Ted Bundy, the notorious serial killer and rapist, was known to receive many love-letters in prison, even after the details of his crimes (exclusively against women and girls) were made public and he was able to marry and conceive a child while incarcerated.

As for later years, schools took a zero-tolerance policy, so that would have cut down on it significantly. With social media use increasing towards the end of the 2000s, fights could have been reduced further because people did not want to end up as a punchline (no pun intended) on Worldstar or Vine.

I experienced way more violence in my late teens and early twenties thanks to drinking in dodgy towns.

Definitely tapered off the last couple years of high school, but some of the rougher kids continued to engage it. Those kids pretty quickly got into serious enough trouble that they ended up in jail, expelled, on probation. That quieted things down a good bit.

This was common for other people who I met later that from developing nations. Not sure if this still happens anymore.

I did encounter some, but it was more like we as kids watched a lot of US media and thought this was how we needed to behave but were more “playing at it” than actually being vindictive.

My one fight in school was with the “toughest” kid in my age group (I was the nerdy outsider they were bonding over to defeat), we duked it out in the yard with half of the school watching, and didn’t get a clear winner. We both got tired and called it quits.

Both got reprimanded of course. Weirdly enough that was the most violence I’ve encountered in my life, period.

I blame video games. Aggressive teens got an outlet where they can establish rankings, troll, be dicks, or defend others, with zero parent supervision.

In my case, since it was done in computer cafes, it had its strong social aspect, with crowds cheering, gangs and clans. Counter Strike was more of a religion to us than anything. And it was so much fun that we didn’t really need “the real thing”.

However, increasingly sedentary lifestyles are definitely part of the problem. Jobs encourage people to sit motionless, of course, but most of our leisure time has been replaced by other motionless activities.

Global obesity rates have also been rising steadily while testosterone levels have trended downward. Obesity is well known to reduce testosterone levels.

There might be additional answers in environmental toxicities, but it's a mistake to ignore the elephant in the room: Lifestyle is a problem.

> For instance, the peak in leaded gasoline use in the late 1970's corresponds to a peak in aggravated assault rates in the late 1990's in urban areas across the United States.

https://en.wikipedia.org/wiki/Lead_poisoning#Violence

Yes, and they address this in the study. They controlled for BMI, among other confounding variables.

You can have muscle if you have low testosterone, but it will develop slower compared to if you had higher testosterone.

I keep finding stuff that links psychological aggression and testosterone in men, but only loosely -- i'd like to read something contrary to that if you have it. [0]:

[0]: https://thepsychologist.bps.org.uk/volume-22/edition-1/testo...

[1] http://openvault.wgbh.org/catalog/V_474CF2C8A20B4173988486AC... (relevant portion min 40-45)

I choose these words for two reasons. First, the ratio of muscle to fat is important for most any metabolic disorder (this means both diabetes and obesity, which are comorbid). Muscles are actively important in metabolic health as they burn calories through use. And contrariwise, among their other problems, fat cells store and secrete estrogens, which is problematic for those that wish to identify as cis male. Clearly some level of the growth cascades that testosterone produces is useful for metabolic health, if not testosterone itself. Else we get into an obesity spiral and limit the development of our own bodies.

Second, high testosterone is often associated with anti-social outcomes like violence. While this is (weakly!) true, this isn't the whole truth. For instance, people given testosterone actually produced fairer deals vs non-blinded placebo.[0] So it seems more appropriate to call testosterone a status regulator than an aggression hormone.

Let's say we avoid the view that no testosterone is good – this would be ad absurdum considering its central role in the body's development. Even if you were to disagree as to basal level of testosterone in 1999, there are clear positive outcomes associated with testosterone which we can organize our sense of what is optimal around; it is possible that we have swung too far, and our current levels are not good enough.

To deny the positive aspects of testosterone, is to deny its usefulness to metabolic health, to regulating status, and maintaining the spiritedness to engage with life.

[0] https://www.lesswrong.com/posts/uRg5Q2vAteDem5b5S/social-sta...

That rumor is false

Which…makes a naïve sort of evolutionary sense. You need some percentage of body fat for your body to kick into reproduction mode.

While it's true that estrogen-like compounds may also have an effect, it takes calories to ovulate and to menstruate.

In college a classmate used the term "skinny fat" to describe himself, same body type you describe. He was within the healthy weight range for his height and frame, but because of poor diet and exercise (primarily exercise) he had a rather high body fat percentage. It's easy to hit that point if you have a halfway decent diet (at least by calorie count) but a sedentary lifestyle (like us at the time, and perhaps more now, living on our computers playing video games and programming). The rest of us were just "fat fat" since our diets (especially sodas, he never drank any and some of us were only hydrated because of them) were much worse than his and we were similarly sedentary.

Higher testosterone leads to more risk taking and other adverse behaviors, as well as increased blood pressure and, anecdotally, "increased aging." I believe it has something to do with collagen synthesis.

You absolutely made the right decision to come off TRT.

Many endocrinologists have blood draw facilities within the practice.

Either way you have to go back to interpret the results and, if appropriate, receive the prescription.

Don't play with your endocrine system people, let alone with testosterone which will make you dependent on it for the rest of your life

I was pretty adamant about giving it a shot, and consulted with an endocrinologist who said the same thing ("it's not low enough to introduce what would become a life sentence of treatment"). After much stubborn research trying to find a legitimate second opinion[1], I finally conceded that he was right.

I'm all for biohacking, but the one-way/ratcheting nature of T therapy specifically should make it an endeavor of last resort.

[1] I say legitimate because you can effortlessly find someone who will agree that you and everyone needs a T boost, and will write you an Rx on the spot if you have the cash. An it will work. It's not that it's a scam, or particularly deadly. The benefits are just very overplayed compared to their permanence, which is downplayed.

Also you'll likely end up infertile.

Just adjusting one's hormone profile to hit some level you have in mind is not as easy as you imply.

I don’t think that’s true. Even birthcontrol requires a prescription.

what kind of filtering?

Because in men you can't.

Tanking your estrogen levels, or having them too high, suuuuuuucks. And the surprise to me was having estrogen come in too low from taking too much aromatase inhibitors. The mood, skin, and libido changes are awful.

I mean, look at Greece now.

We have been eating meat and saturated animal fat much longer than abundant carbohydrates have even existed. Combine this with the fact that all your health problems go away on carnivore, it’s pretty obvious that we were designed to eat meat.

It isn’t until you go carnivore that you realize how a plant based diet is actively trying to destroy your mouth and take away your teeth. Do you think ancient humans were brushing their teeth and flossing?

And it’s not just that your health problems go away. You become practically super human. You get ripped without going to the gym. Reports of higher energy and mental clarity are practically universal.

I know it sound crazy and that’s why I qualified my comment the way I did. There are hundreds of video testimonies that back up what I say on meatrx.

One of the things that is also universal is an increase in testosterone and aggressiveness.