A troubling rise in the number of young people in the U.K. reporting mental health difficulties like depression and anxiety means they are now more likely to call in sick than aging Gen Xers who are 20 years their senior, in a surprising turnaround for historic wellness trends. 

That growing mental health crisis is beginning to have a major impact on Gen Z employees’ career prospects, according to research by the think tank Resolution Foundation (RF).

Gen Z now getting sicker than 40-year-olds

Research from the RF finds that more than a third of young people aged 18 to 24 suffer from what is described as a “common mental disorder,” (CMD) like depression, anxiety, or bipolar disorder. The figure is well above the 24% of young people in 2000 who lived with a CMD.

That jump has been “turbocharged” by a mental health crisis among women. Two out of five women in the U.K. are likely to report a CMD, compared with a quarter of men. 

While there are theories about the causes of this surge, from the loss of vital public services to the falling stigma around talking about mental health, what can’t be debated is the real-world impacts of increasing instances of poor mental well-being.

RF analysis has found that the number of young people taking time off work due to ill health has doubled in the last decade. 

The effects on work outcomes are becoming clear. People living with mental health difficulties are more likely to be working in low-paid jobs compared with their healthier colleagues.

The most worrying part of that trend for policymakers is that it is creating previously unheard-of generational dynamics. For example, young people are now more likely to be absent from work because of illness than people who are 20 years older.

That generational divide is leading to workplace schisms that are hurting productivity. A study by the London School of Economics and consulting firm Protiviti found more than a third of Gen Z employees were self-reporting themselves as being unproductive. 

The researchers put the cause of this low productivity down to a communication breakdown between young workers and their older managers. 

It’s also impacting the U.K. economy. Research from health insurer Vitality found Gen X and millennial workers were missing the equivalent of one day of work every week due to poor mental health. Vitality estimated this was costing the British economy £138 billion ($176 billion) per year.

“Youth worklessness due to ill health is a real and growing trend; it is worrying that young people in their early 20s, just embarking on their adult life, are more likely to be out of work due to ill health than those in their early 40s,” RF researchers said. 

Universities becoming ‘hotbeds’ for mental health issues

According to the RF, young Gen Xers surveyed in 2000 had the lowest proportion of CMD cases on record.

And while it might be easy to blame the recent rise on the effects of the COVID-19 pandemic, the issues are more deep-seated and the culmination of longer-running trends.

One of them is an increasingly stressful education environment. The RF says universities have become “hotbeds” for mental health problems. Past research shows three out of five students are living with a mental health disorder.

At the same time, research shows that a college education remains people’s best chance of landing higher-paid careers, creating a double-edged sword where young people increasingly run the gamut of risking their mental health for better job outcomes.

Students also receive more mental health support from their universities, compared with non-university students who have fewer options to seek out support.

Gen Z women most affected

RF’s research made a striking realization that young women are now 1.6 times more likely than men to take time off work due to ill health. It reversed a trend of young men taking more time off in the 2010s, and the dial has only shifted thanks to a steep rise in female illness in the last couple of years.

Gen Z women are consistently reported as the most likely to be suffering from mental health disorders. Psychologist Jean Twenge, Ph.D., told Fortune last year there is a clear correlation between the rise of smartphone use and declining levels of mental health.

Teenagers hitting college age report the biggest instances of poor mental health. Nearly a third of females ages 17–19 have a probable mental disorder, according to the RF.

The think tank urged sectors employing large numbers of young people to spearhead initiatives to hire more “mental-health aware” managers to improve the outcomes of tomorrow’s leaders.