For every dollar an American man makes, his equally qualified female counterpart makes just 82 cents. According to a new study by Mailman School researchers, the consequences of this wage gap extend beyond the checking account: women who earn less than their male peers are at greater risk for anxiety and depression than those who are fairly compensated.

Jonathan Platt, a PhD student in Epidemiology, and colleagues looked at a survey of 22,581 working adults Americans, finding that among women whose income was lower than their male counterparts, the odds of major depression were nearly two-and-a-half times higher, and odds of anxiety were more than four times higher, than men matched for age, education, occupation, family composition, and other factors. Yet when women’s income was greater than their male counterparts, women’s odds for having anxiety or depression was nearly equivalent to men.

It's a startling fact: women in the U.S. are nearly nearly twice as likely to have depression or anxiety than men. Past research looking to account for this disparity explored factors like differences in sex hormones and coping mechanisms, but so far nothing has provided an adequate explanation. In their new study published in Social Science & Medicine, the Mailman researchers find that higher rates of these mental problems in women may in part be explained by lower pay.

“Our results show that some of the gender disparities in depression and anxiety may be due to the effects of structural gender inequality in the workforce and beyond,” says Platt, first author of the paper. “The social processes that sort women into certain jobs, compensate them less than equivalent male counterparts, and create gender disparities in domestic labor that have material and psychosocial consequences.”

Income is a strong predictor of health outcomes, mental health included; the lower the income, the greater the risk. But according to Platt and his co-authors, the disproportionate rate of anxiety and depression diagnoses in women is about more than just material resources. For one, women spend more time on domestic roles than men, an added burden that can lead to anxiety and depression. On top of that, there is an insidious psychological process that leads women to blame themselves for different expections around their jobs and how they're compensated.

“If women internalize these negative experiences as individual-level issues, rather than the result of structural discrimination, they may be at increased risk for depression and anxiety disorders,” says Platt.

“Our findings suggest that policies must go beyond prohibiting overt gender discrimination,” says Katherine Keyes, assistant professor of Epidemiology and senior author. “While it is commonly believed that gender differences in depression and anxiety are biologically rooted, these results suggest that such differences are much more socially constructed than previously thought, indicating that gender disparities in psychiatric disorders are malleable and arise from unfair treatment.”

Keyes notes that policies such as paid parental leave, affordable childcare, and flexible work schedules may ameliorate some of this burden, although more research into understanding the ways in which discrimination plays a role in mental health outcomes is necessary.

“Greater attention to the fundamental mechanisms that perpetuate wage disparities is needed,” says Keyes, “not only because it is unjust, but so that we may understand and be able to intervene to reduce subsequent health risks and disparities.”