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Today's men have less testosterone than before. And we don't really know why

Is masculinity in crisis? The issue has sparked countless debates and ramblings over the last decade

Today's men have less testosterone than before. And we don't really know why
Today's men have less testosterone than before

Is masculinity in crisis? The issue has sparked countless debates and ramblings over the last decade, as a result of the changing roles of men in society and the push of feminist and conservative thought. But beyond theory, there is little data that evidences a profound transformation between the men of yesterday and today. Of course, among the shortages there is a clear trend: testosterone seems to have fallen into decline.

Studies. This is illustrated by this study published in The Journal of Sexual Medicine. After analyzing the hormonal levels of more than 4,000 young Americans between 1999 and 2016, the researchers discovered that men born during the past decade had lower levels of testosterone than those who entered the world during the first years of the 21st century. All this controlling for age or body mass index.

Trend. It is not the first work that points to something similar. As early as 2007, a study published by New England Research identified a 17% drop in testosterone levels between 65-year-old men in 2002 and 65-year-old men in 1987. Another research focused on more than 5,000 Danish men illustrated pointed out that the same direction. Today's men have less testosterone than yesterday's, down ~ 0.5% per year.

Limitations. We know that testosterone tends to decrease with age, and the few scientists dedicated to the subject have observed similar decreases in all cohorts. In spite of everything, as the Danish work explains, there are still methodological problems derived from the reliability of the samples and the methods used in each generation (the studies are based on information collected over decades).

Why? It's the million-dollar question. Here are some possible answers: from quitting tobacco (things in life, it turns out that nicotine stimulates the production of testosterone) to moving towards an increasingly sedentary life, passing through air pollution (another of its many effects harmful to health) to a wide range of transformations in the way we live and interact.

Today's men perform less in physical tasks and lead a more sedentary life. Factors that may be related to the drop in testosterone. In either case, the answers to the question are still doubtful. We are not clear why this is happening.

What does it mean? On the one hand, more and more men are turning to drugs that boost testosterone levels. On the other, a vicious cycle: obesity among men is on the rise, which depresses testosterone, and in turn increases the chances of developing obesity. Less testosterone also means lower libido (we are also having less sex than before), lower physical energy, and, although the evidence here is more tenuous, more risk of depression.

Weak ties. None of this will make our societies more peaceful or less prone to violence. Despite the old mantra hatched during the 1970s and 1980s, the connection between testosterone and violent men is rather weak. It plays a role in amplifying the dynamics of competitiveness already existing in society, but it is not a hormone that predicts the levels of aggressiveness of any man. Is this related to the "crisis of masculinity"? These are two issues that, today, walk-in parallel.

It remains to be seen that lower testosterone will change our notions of "masculinity" as profoundly as the social, cultural and economic transformations are doing.

What if the link between testosterone and violence was an unfair topic spread by bad science?

Rebecca M. Jordan-Young, a sociomedical scientist and popularizer at Columbia University, and Katrina Karkazis, a cultural anthropologist at New York University, recently published a book titled Testosterone: An Unauthorized Biography, a fairly self-explanatory title on a volume that, in the style of other recent revisionist essays, aims to dismantle some clichés established in popular knowledge and promoted by scientific analyzes that were not entirely rigorous from decades ago.

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See all posts by JOHN ANDERSON