NEW YORK — Working the night shift as a young adult probably doesn’t seem that bad, right? You’re young and energetic, the hours give you plenty of free time during the day — what’s not to like? Well, a new study finds all of these night shifts and irregular schedules can affect your health decades later. A study from New York University finds that “volatile work schedules” in your 20s can lead to sleep issues and poor physical and mental health by age 50.
Moreover, it turns out that the traditional nine-to-five workday was the most protective health-wise over the course of someone’s life. Compared to those working the typical Monday through Friday, 9 a.m. to 5 p.m. schedule, young adults working at night or on other volatile schedules slept less and worse. They were also more likely to report feelings of depression almost 30 years later.
Wen-Jui Han from NYU used data from The National Longitudinal Survey of Youth-1979 (NLSY79) to reach these conclusions. The survey includes information about more than 7,000 people throughout the U.S. over a 30-year period. Only one in four people (26%) always worked a stable schedule with standard hours.
Over a third (35%) “mostly” worked a normal schedule, while 17 percent started on a standard schedule in their 20s before transitioning to a volatile schedule in their 30s. Volatile schedules include working evening hours, night shifts, or schedules where the daily hours are constantly changing. Only 10 percent of the participants did not work during the study period.
The biggest differences in health appeared among workers who started their careers working normal hours before shifting to a volatile schedule in their 30s. In fact, the impact on health was similar to the effect of only having a high school-level education.
Han also found that Black Americans were more likely to have volatile work schedules, which led to poorer health during middle age. Overall, the study, published in PLOS One, finds that not being able to work the typical nine-to-five may lead to poor sleep quality, physical fatigue, and emotional exhaustion. All of this can leave the body vulnerable to disease later on.
“Work that is supposed to bring resources to help us sustain a decent life has now become a vulnerability to a healthy life due to the increasing precarity in our work arrangements in this increasingly unequal society. People with vulnerable social positions (e.g., females, Blacks, low-education) disproportionately shoulder these health consequences,” Han concludes.
Previous studies have found even more issues tied to working at night. A 2023 report on 50,000 people working outside of the typical nine-to-five found shift workers may suffer from impaired memory and cognition by middle age. The highest rates of cognitive impairment were found among employees who reported working more night shifts at their current job or working the night shift at their longest-tenured job.
One 2021 study even found a link between working overnight hours and various health conditions, including irregular heartbeat and cancer. Scientists at Washington State University’s Health Sciences sleep laboratory found that a human’s 24-hour rhythm is disrupted when you regularly work at night. This causes abnormal activity in certain genes linked to cancer development, increasing the risk of DNA damage.
De nada! I worked swing/graveyard for >25 years. In retirement I’m up by 6:00am every morning, sometimes kind of annoying, but I adapted. Working all the graveyard calls is what got a new retirement home in Florida, ten minutes from the beach.