Does your testosterone level determine how successful you'll be?
A new study claims the hormone doesn't, in fact, give men an edge.
Photo: Simone Pellegrini / Unsplash
Dr Amanda Hughes from the University of Bristol is the author of the study.
Previous studies showing links between higher testosterone and socioeconomic success focused on small sample sizes and often just one profession such as financial trading, Dr Hughes tells Jim Mora.
This new study, based on data from more than 300,000 British adults, tells us a lot more about testosterone than we previously knew.
“For example, showing executives with higher testosterone have more subordinates doesn’t tell you anything about which way the causal arrow is going. It doesn’t tell you anything about whether having more testosterone gets you more subordinates or having more subordinates raises your testosterone.
“I think in the popular consciousness people have tried to extrapolate from findings about testosterone … to men widely and jobs more widely and how successful people are in their careers.”
The University of Bristol researchers first identified genetic variants that predict people likely to have higher testosterone, then looked at whether those people had higher incomes, higher educational qualifications and were more prone to risk-taking.
“That means if you see an association of having the high testosterone version of the genes with something like income that is much stronger evidence that testosterone has a real causal influence on income and not the other way around.”
This method of research provides less certainty on the correlation between high testosterone and success or risk-taking, Dr Hughes says.
“In fact, the men in our study that had higher testosterone were more likely to describe themselves as people who were willing to take a lot of risks but having said that, when we dug into this a bit further, it doesn’t seem to clearly support that the testosterone causally influences the risk-taking, it could be the other way around.”
The researchers' measure of what constitutes 'risk-taking' was somewhat crude, Dr Hughes says, and a finer measure or an objective assessment might have provided more evidence for a causal link with testosterone.
The data suggested testosterone levels had no substantial effect on whether a person was successful, she says.
“We didn’t definitively show there was absolutely no influence of testosterone on these things but what we were able to do is show that it’s unlikely to be anything other than quite small. Our results suggested that a lot of the observed link between testosterone and success is explained by other mechanisms.
“Some of the previous studies were specifically looking [at professions] … where maybe some of the character traits linked to testosterone would be particularly important.
“I think what we wanted to do was expand that question to see how important it was likely to be for normal men and normal women.
“It could work differently in quite specific professions, like mountain climbing. Had we looked in a huge sample of just mountain climbers, we might have had different results.”
It's important to note that testosterone levels are influenced by many factors, she says.
“[Testosterone is] potentially affected by epigenetics, also just simple things like the time of day, how old you are, lots of environmental factors, your health, stress levels."
We know chronic stress can lower testosterone levels, Dr Hughes says, so stress from socio-economic disadvantage could be one of the reasons some people have less of the hormone.
Future studies may reveal the importance of testosterone has been "overblown".
“I’d like to think that some people would be comforted to hear that your testosterone level is not the be-all and end-all of where you’re going to end up in life at all.”