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Working late nights and variable schedules when you’re young is linked with poor health and depression at 50, a new study finds.

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Working late nights and variable schedules when you’re young is linked with poor health and depression at 50, a new study finds.

simonkr/Getty Images

Feeling burned out and looking for reasons to work less? A new study shows that working nights and volatile schedules in young adulthood can leave you vulnerable to depression and poor health in middle age.

The research examined the work schedules and sleep patterns of more than 7,000 Americans interviewed over three decades, from the ages of 22 through 50. To the surprise of the study’s author, NYU Silver School of Social Work professor Wen-Jui Han, only one-quarter of the participants worked exclusively traditional daytime hours.

The remainder – three-quarters of the sample of American workers born in the 1960s – worked variable hours. Those with more volatile work schedules, including night hours and rotating shifts, reported less sleep and a greater likelihood of poor health and depression at age 50 than those with more stable schedules and daytime hours.

“Our work now is making us sick and poor,” Han said in a Zoom interview. “Work is supposed to allow us to accumulate resources. But, for a lot of people, their work doesn’t allow them to do so. They actually become more and more miserable over time.”

Han would like her research — published last week in PLOS One — to prompt conversations about ways to “provide resources to support people to have a happy and healthy life when they’re physically exhausted and emotionally drained because of their work.”

She was one of those employees. In her 40s, when Han was up for tenure, she worked 16-hour days, taking time off only to eat and sleep, though not sleeping nearly enough. Her doctor warned her that her physical condition appeared more like that of a woman in her 60s.

She was overworking like many young professionals who have embraced hustle culture and work around the clock.

“We can say they voluntarily want to work long hours, but in reality, it’s not about voluntarily working long hours,” Han said. “They sense that the culture of their work demands that they work long hours, or they may get penalized.”

She says the participants in her study who sacrificed sleep to earn a living, suffered depression and poor health, she said. “When our work becomes a daily stressor, these are the kind of health consequences you may expect to see 30 years down the road.”

Black men and women and workers with limited educations disproportionately shouldered the burden of night shifts, volatile work schedules and sleep deprivation, the study shows.

White college-educated women with stable daytime work reported an average of six more hours of sleep a week than Black men who had not completed high school and who worked variable hours for most of their lives, Han’s study found.

And Black women who did not complete high school and switched from regular daytime hours to volatile employment in their 30s were four times more likely to report poor health than white college-educated men with stable and standard daytime work lives.

The study shows a relationship between working nights and rotating shifts with poor sleep and poor health, but it cannot prove one caused the other. That said, the U.S. Centers for Disease Control and Prevention links insufficient sleep with chronic diseases, such as diabetes, heart disease and obesity, and African Americans are more likely than whites to suffer from these diseases.

How much a person needs to sleep to remain healthy depends upon age, but the American Academy of Sleep Medicine and the Sleep Research Society recommend that adults between 18 and 60 years old get at least seven hours of shut-eye a night.

Dr. Alyson Myers appreciated the new study’s focus on the connection between work schedules, sleep and poor health.

The study findings confirmed what she sees in many of her diabetes patients, who often get no more than five hours of sleep after they work night shifts. She counsels them to try to switch to days, and when they do, their health improves, the endocrinologist and professor at the Albert Einstein College of Medicine said.

Prior research has shown that sleep, diet and social habits required to work nights and rotating shifts, can increase the risk of developing diabetes. In 2019, Blacks were twice as likely as whites to die of diabetes, according to the U.S. Department of Health and Human Services.

“Poor sleep is a risk factor for diabetes that very often we do not talk about,” said Myers, who was not involved in the study. “One of the things that I have to preach to my patients about is that working nights, and if you get only four or five or less hours of sleep, that’s going to increase your risk of diabetes and also worsen your glycemic control.”

One patient was angry with her when he followed her advice, switched from working nights to days and as a result had to contend with commute traffic. “But,” she said in a Zoom interview, “we actually got better control of his blood sugar when he switched to working the day shift.”

About 16% of American workers were employed outside of daytime hours in 2019, according to the U.S. Bureau of Labor Statistics.

Many of the participants in Hans’ study who had volatile work schedules tended to have part-time jobs, in some cases multiple part-time jobs. “Unfortunately,” Myers said, “the trend for a lot of these people is that they have to work more than one job to survive.”

Ronnie Cohen is a San Francisco Bay Area journalist focused on health and social justice issues.