More than 800,000 people around the world kill themselves each year, and millions more try but fail. This puts suicides among the top preventable causes of death in the world. And from Albania to Zimbabwe, in every country, men commit suicides in greater numbers than women do.

There are probably many factors as to why this is the case. But Rory O’Connor of the University of Glasgow believes that he may have found the one factor that contributes to this gender bias the most: social perfectionism.

Men feel they have to provide or they have failed. A 2014 study (pdf) shows that, despite decades of progress on gender inequality, expectations of what it means to be a man are stuck in the 1950s. On social perfectionism, O’Connor says in Mosaic:

It’s nothing to do with what those people actually think of you. It’s what you think they expect. The reason it’s so problematic is that it’s outside your control.

Even in the developed world, where gender equality is not as bad as in developing countries, most men still see themselves as being responsible for providing and protecting their family. Of course, some women are social perfectionists too. But men’s social perfectionism is much more harmful.

“A man who can’t provide for the family is somehow not a man any more,” Roy Baumeister of University of Florida says in Mosaic. “A woman is a woman no matter what, but manhood can be lost.”