What we earn can affect our mental wellbeing, especially when we compare ourselves to those around us – and it can negatively influence male mental health.

"It stings your pride a little bit that your wife's the one out making all the money," said Dave, of his status as a stay-at-home dad.

"I'm, you know, a guy's guy... you tell them you stay home, and... they think you're some feminine dude," said Tom. Both were participants in an in-depth research study where both men and women were interviewed about the impact of the women in the relationships being the breadwinners.

Another, Brendon, had good reason to feel judged: family members labelled him "the house bitch".

These are but three examples of the judgement experienced by men who don't have jobs outside the home, and whose female partners are the primary earners.

In the study, the men said they felt judged partly because it's long been assumed that men are the main breadwinners in society. However, an increasing number of women are outearning their male partners, and this gradual rise of female breadwinners is revealing that who earns the money has lasting and influential impacts on power dynamics both at home, and in wider society.

A key reason these changing family dynamics are so influential is because money is so closely tied to power. When men aren't the highest earners in their household – but are expected to be by some sections of society – it can lead them to feel disempowered, decreasing mental wellbeing and even increasing the likelihood of divorce.

Overall, men still tend to outearn women and among married couples with children, and women do more childcare and housework than men, a stubborn discrepancy found globally. In part this is thought to be due to gender expectations, but in some cases it may also reflect an economic necessity where the higher earner's career tends to be prioritised, so women are more likely to step back into part-time, flexible roles.

Despite the increase in breadwinning women, gender attitudes to paid work and roles at home have been slower to change. Even if women are the higher earners, they still do more housework and childcare than lower-earning male partners. And while among some age groups there's been an increase in support for gender equality, men still show lower satisfaction if they are out-earned.

An increasing body of research shows that it can affect a man's self-esteem and happiness if their female partner earns more than them. But how serious is the problem really? And what can be done to help men adjust to their new reality?

It's a little taboo for men to even talk about the impact of their female partner becoming the breadwinner. They might feel supportive of their partner's career, whilst at the same time feeling that they aren't fulfilling their role as "breadwinners" because many outdated assumptions of masculinity remain prevalent.

This is especially true when men inadvertently become stay-at-home fathers due to job loss or relocation, rather than choice. Harry Bunton, an ex-consultant and now rising social media influencer based in Sydney, Australia, recently lost his job. He posted on social media afterwards to thousands that his "values as a man, husband and father" were impacted.

"It makes sense to me why there's such a high rate of depression, and worse, in that population. When things don't go to plan it can be really devastating and can really challenge your ideas of what it means to be a man," Bunton wrote. "My hope is that sharing this story is that people can identify with it and their value isn't predicated on events like this… I feel almost empowered to be the dad that I want to be."

While Bunton took a positive approach to the change in his lifestyle, he exemplifies that how much a man earns relative to his partner can affect their mental wellbeing. For instance, one recent study of heterosexual couples in Sweden looked at 10 years of earnings data as well as mental health diagnoses to look for patterns. The researchers found that at the point when wives began to outearn their male partners, there was an uptick in mental health diagnoses among men. While there was an increase of up to 8% in mental health diagnoses for all participants whose partners earned more – including women – there was a more pronounced rise of up to 11% for men overall.

While writing my upcoming book, Breadwinners, I spoke with Demid Getik, an assistant professor in the Economics Department at Durham University who led the study, to find out more. He told me that while we may no longer hear it explicitly stated that the man should earn more, these expectations are still highly prevalent. The increase in mental health diagnoses in men whose partner has begun earning more, says Getik, could also be an indication that these couples are showing decreased relationship satisfaction, though his data did not........

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