I unfortunately do not have a source for this because I read it in an academic anthropology paper many years ago, but... This is why I will never worry about my cis-male partner's testosterone levels, and I hope that others read this and start questioning why "high testosterone" in cis men is considered a good thing.
The paper in question noted that older adult men have lower testosterone than their teen and young adult counterparts. It freely admitted this.
But it attributed the phenomenon to a net gain for humanity, and I still believe the arguement made:
Lower testosterone is an evolutionary requirement for the continuation of our species.
The paper correlated lower testosterone primarily with men who had children. (Older men without children generally had higher testosterone levels than their fatherly counterparts, though still lower than younger men.)
The author argued that, much like babies looking like their sperm donor is one piece of species preservation, so is a biological imperative to reduce testosterone levels: because first, men who believe that a child is theirs will be more likely to stay and protect them (rather than fight unnecessarily or seek another sexual partner) and then because men with lower testosterone will make fewer reckless decisions and be more even-tempered for child-rearing years.
Now obviously this isn't universal, and my relaying of the original article has many gaps in it due to the intermittent years slowly stealing my specific memories of what I read, but the overwhelming feeling I still have when I think of that paper is this:
It was--and still is--an evolutionary advantage to our species for men to naturally decrease their testosterone levels as they grew older. Coupled with emotional growth, it can help men trend more towards rationality and well-considered opinions. Men with lower testosterone feel safer to those around them and tend to be more diplomatic.
So why do so many herbal supplement and snake oil companies (and now the freaking government) want men to take testosterone regulators?
Well, for one, most of those products are actually bad for any cis women who come into consistent direct contact with a man on snake oil. Supplemental testosterone oozes from your pores and can cause health problems for your afab partner. And two... they don't want you to think. They want you to feel constantly emasculated and defensive at your so-called "low testosterone" because then you are easier to control. In the case of snake oil companies, they can control you into buying more products. In the case of the current military testosterone kerfuffle...
Let's just say it doesn't look good from where I am sitting.
Anyways, the point of all of this is that I hope cis men worry less about low testosterone and worry more about other aspects of their emotional, mental, and physical health, and particularly about the health of our society.
We don't need you to be macho. We need you to be good people.












