• Husbands tend to experience the least stress if their wives earn about 40% of their total household income, according to a new study that examines data from about 6,000 American couples.
  • But men get more anxious once their wives earn more than that, especially if husbands are entirely financially dependent on their wives. 
  • When it comes to money, traditional views of gender roles "can be dangerous for men's health," the economist behind the study said. 

Men have higher levels of stress if their wives earn more than 40% of their household's income, a sign that gender stereotypes can have a harmful impact on some husband's mental well-being, a new study finds. 

Husbands also suffer from higher stress when they are the sole breadwinner, a signal that bearing the entire financial responsibility for a family's well-being also causes anxiety, the study noted. The survey, conducted by the U.K.'s University of Bath, examined responses from about 6,000 heterosexual American couples over a 15-year period, from 2001 to 2015. 

The findings come at a time when about a third of U.S. women earn as much as or more than their husbands, compared with about 12% in 1980, according to the Pew Research Center. Women have also narrowed the gender pay gap — although it remains at about 80 cents for every $1 earned by men — and now represent a majority of college grads. 

Even so, gender norms about men and money remain entrenched, which can lead to problems for men's mental health, the study suggests.

"There's a kind of a sweet spot when men are most comfortable when women make 40% of the total income," said Joanna Syrda, an economist at the University of Bath's School of Management, in a YouTube interview about her research. "Once her income rises past that point, their distress rises."

The research indicates that traditional views of gender roles "can be dangerous for men's health," she added in a statement.

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