Researchers say men who see women as unequal or as sex objects can develop serious mental health issues.

Sexism harms women and society at large.

It can also be psychologically toxic to the perpetrators of sexism themselves.

For the past couple of decades, psychologists have been uncovering a link between traditional masculinity and poor mental health.

Now, a new meta-analysis published in the Journal of Counseling Psychology confirms that link and adds some details about which aspects of so-called “toxic masculinity” are most damaging to mental health.

Researchers from Indiana University, and Nanyang Technological University in Singapore, combined the data from 74 studies comprising nearly 20,000 subjects.

They concluded that those who conformed closely to traditional notions of masculinity were more likely to have poor mental health outcomes.

They were also less likely to seek help.

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The large data set allowed the researchers to examine which 11 masculine norms were most harmful.

The two aspects most closely related to sexism, which psychologists refer to as “playboy” and “power over women,” were among those most closely linked to poor mental health outcomes.

Those who conform to the so-called “playboy” norm of masculinity, see women as sex objects and typically say they’d prefer to have many sex partners.

Those who conform closely to the “power over women” norm see women as unequal to men and in need of a controlling masculine influence.

A third masculine norm closely linked to poor mental health is “self-reliance.” Men who adhere to this norm prefer to solve problems themselves and not to ask others for help.

The study doesn’t establish how these factors relate to poor mental health outcomes.

However, Y. Joel Wong, an associate professor of counseling psychology at Indiana University, and the lead author of the study, argues that all of these masculine norms limit the social potential of those that conform to them.

He told Healthline these attitudes toward women might leave the men who exhibit these norms out of touch with their friends and coworkers and, perhaps most importantly, their wives and girlfriends.

“Perhaps 40 years ago you could behave in a sexist way and people would not speak out against you,” said Wong. “Today, however, people around you would speak out and you’d get pushback,” he said.

At the very least, people may avoid you.

“Either way, there are negative interpersonal consequences. And I think these ultimately boomerang on the perpetrator of sexism to make things more stressful for them,” Wong said.

Self-reliance can also freeze men out socially.

“In today’s interdependent world, self-reliance is increasingly problematic because trying to go it alone, having difficulty asking for help, makes it hard to get things done,” Wong said.

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These masculine norms correlated with increased mental health problems like stress, depression, and other psychological problems, but the greatest negative effect was on social functioning.

These men are more likely to feel lonely, hostile, and less likely to have the benefit of strong, loving social bonds.

Wong thinks these men’s relationships with the women in their lives may be the biggest factor leading to these negative effects.

He points to another study in which he and his colleagues looked at what he calls the “zero sum gender” beliefs of men — the idea that if women gain rights, men lose them, for example.

In that study, Wong concluded the reason men who had these beliefs had poorer mental health was because they had poorer relationships with their wives or girlfriends.

Ronald F. Levant, a psychology professor at the University of Akron and a leading researcher in this field, said Wong’s current study is a powerful confirmation of this phenomenon. But he also says that masculinity norms are in flux.

“Younger men are picking and choosing which masculine norms they are going to adhere to,” Levant told Healthline. “A growing number of men are rejecting these norms.”

On the other hand, Levant cites the growing influence of the Alt Right, a white nationalist movement that embraces traditional masculinity, in pushing the expression of explicit biases out in the open.

This year’s presidential election “unleashed and energized varying groups of prejudiced people,” he noted.

“It’s going to be difficult to put the genie back in the bottle,” Levant said.

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There is effective help available for men who experience these mental health problems related to their views of masculinity.

Counseling can help them develop better social skills and deal with mental health problems like stress, depression, and anxiety.

The problem is, as Wong and his colleagues found, these men are less likely to seek help. And that poses challenges for mental health professionals and loved ones who want to help.

“This is kind of a double whammy,” said Wong. “These are the very same people who need mental health treatment who are not getting it.”

But Wong says there are some helpful strategies to get them to seek help.

One is providing a masculine model who has sought counseling. Try to find a man who this person respects, an uncle or a friend, who has experienced a similar issue and can discuss it with them.

Another strategy Wong suggests is to try a less stigmatizing approach like coaching or mentoring, rather than counseling or therapy. A life coach who doubles as a counselor might focus on being more effective or successful while also dealing with the underlying mental health issues that hold men back.

Another option is online counseling, which is more private and may be a good first step.

“If all else fails, buy a self-help book as a Christmas present,” Wong says.

He recommends “Feeling Good,” by David D. Burns, M.D. It addresses issues like depression through structured strategies that might appeal to men, rather than emotional introspection.

Some of these strategies might even help change these men’s attitudes toward women, ending the cycle of harm. And that may benefit the women in their lives, too.