Researchers from the University of Durham have revealed intriguing insights into the impact of income disparity on mental health within heterosexual relationships, revealing a less glamorous side to this rising trend.In a study analyzing incomes and mental health among couples in Sweden, scientists found that women taking on the role of primary breadwinner significantly increased the risk of mental health issues for both partners—most notably for men. The findings highlight a persistent societal tension, even in progressive nations like Sweden.“The share of couples where the wife outearns the husband is increasing globally,” the researchers noted. “Crossing the threshold where the wife starts earning more significantly increases the probability of receiving a mental health diagnosis. In the most restrictive specification, the likelihood increases by approximately 8% for the whole sample and by 11% for men.”The study, published in The Economic Journal and led by Demid Getik, followed 2021-married heterosexual couples over a decade or until their marriages dissolved—approximately 20% of the sample. The average age of participants was 37. Researchers discovered that while both partners' mental health benefited from higher absolute incomes, the dynamic shifted negatively when wives surpassed their husbands in earnings.Interestingly, male participants were more prone to substance-related diagnoses, while women exhibited heightened risks for stress-related and neurotic disorders. This dichotomy sheds light on the psychological pressures tied to societal expectations of traditional gender roles.“Mental health is a crucial outcome linked to a host of important economic and life outcomes,” the researchers emphasized. “In this study, we find tangible evidence of relative income in couples playing an important role in mental health outcomes, even in an ostensibly more egalitarian society like Sweden.”The researchers refrained from drawing conclusions about the causes behind these findings. However, Mr. Getik explained to MailOnline: “From earlier literature, it seems likely due to a consistent preference for the male partner to earn more in a couple. It’s a bit more difficult to say to what extent that preference comes from women or men. What is interesting, though, is that you still see this in a country like Sweden, which prides itself on its gender parity.”Also read: Hyderabad student orders via Blinkit, Zepto and Swiggy to see who delivers quickest. Here's who won