This week many are marking International Men’s Day (IMD, November 19), an initiative to raise awareness about men’s well-being. To be honest, I used to regard IMD with a dose of scepticism. Does the world really need a male equivalent to International Women’s Day (March 8th), which celebrates the social, economic, and cultural achievements of women?

My views changed a few years ago, when one of my best friends committed suicide. He was in his early forties and father of a beautiful son. My friend suffered from depression but did not seek professional help. When he finally did, it was too late. Our attempts to get him back on track failed miserably.

This brings me to what the World Health Organisation calls the male health gap. Across the world, men are almost twice as likely to commit suicide than women. They also engage more in unhealthy and risky behaviour, including smoking, heavy drinking, and violence.

Not surprisingly then, women typically live six years longer than men do – and they do so in better health. Moreover, this gender gap in life expectancy has only widened over the past decades. And while part of this gap reflects ‘nature’ (testosterone drives risky behaviour, for example) ‘nurture’ plays a key role too. Boys, more so than girls, are still taught to be self-reliant, assertive, competitive, and in full control of their emotions (‘to man up’).

Teaching such masculinity norms to boys not only contributes to risky and ‘macho’ behaviour by men, it also prevents men from asking for help when they need it. Men are less likely to visit a doctor when they are ill, they are less likely to report the symptoms of an illness, and they take fewer precautionary health measures. The COVID-19 pandemic illustrates this nicely. Most of us have noticed the difference between the attitude towards COVID-19 of, say, Donald Trump and Jair Bolsonaro and the approach of leaders like Angela Merkel and Jacinda Ardern. Recent medical research confirms that ‘macho’ men, those who adhere to traditional masculinity norms, are less likely to wear a face cover or to take other protective measures against COVID-19.

Curious to find further evidence on the effects of masculinity norms on men’s health, I recently teamed up with fellow economists Pauline Grosjean and Victoria Baranov. We first had a look at Ten to Men, a survey that not only measures to what extent individual boys and men adhere to masculinity norms but that also contains data on these men’s health behaviour. As expected, we found that macho men are more likely to admit they have engaged in intimate partner violence; to have thought about, planned, or attempted suicide; to display signs of depression; and to engage in risky health behaviour such as heavy drinking or taking hard drugs. These men were also less likely to consult a GP, a clear sign of help avoidance.

Yet, as any economist will tell you, correlation does not equal causation. Would it be possible to find out whether masculinity norms actually cause unhealthy behaviour? To investigate this, Pauline, Victoria and I used detailed data from Australia’s past as a penal colony. During the 18th and 19th century, the majority of Australia’s settler population consisted of British convicts. The vast majority of these convicts were men. Yet, there was also considerable local variation across Australia in the number of men for every woman, the sex ratio. We expected that in areas with the most skewed sex ratios, where men had to compete intensely to gain access to the few available women, stronger masculinity norms emerged.

These local norms may have persisted over time. Is it still possible to detect their long-term consequences? It is. We find consistent evidence that areas that were heavily male-biased in the past (though no longer in the present) remain characterised by more violence, male suicide, and other negative health outcomes for men. In these areas, boys (but not girls!) are also more likely to be bullied in school, pointing to peer socialisation as a mechanism through which masculinity norms are passed on.

Both personal experience and recent research have therefore convinced me of the dire consequences of men avoiding healthcare and mental help. If International Men’s Day can help to address these issues, it may not be such a bad idea after all.