The Graveyard Shift Is the Worst for Your Heart

People who work various shifts are at high risk for heart attacks.

If you work the night shift, you may want to reconsider your line of work for the good of your heart.

In the largest analysis of shift work and vascular risk, researchers have found that people who work the graveyard shift are at a significantly increased risk of suffering a stroke or heart attack. The findings may have implications for the future of public policy and occupational medicine, according to researchers.

In a study involving more than 2 million people, 26,171 people suffered some sort of coronary event, a heart attack, or a stroke, caused by lack of blood to the brain. Compared with people who work normal business hours, people whose jobs involved working various shifts, such as in the medical field, were associated with a 23 percent increased risk of heart attack, 24 percent increased risk of coronary events, and 5 percent increased risk of stroke.

People who worked the night shift in particular were associated with the most significant risk of suffering major vascular problems, at 41 percent. The researchers noted that findings were adjusted based on participants’ lifestyles, behaviors, and socioeconomic status.

Shift work has long been associated with an increased risk of health problems. It can disrupt one’s circadian rhythm, sleep schedule, and work-life balance. In fact, a previous study concluded that just one overnight shift is enough to increase one’s blood pressure and cause an irregular heart rate. In addition, research has proven that night-shift workers, despite putting in the same amount of hours as daytime employees, tend to get fewer hours of sleep.

While the findings certainly call for an air of caution when it comes to shift work, there is a small silver lining: Shift work in general was not associated with increased risk of mortality over the course of the study. Still, researchers pointed out that since there is a wide variety of shift work jobs, the overall risks for the employees’ health remain at an all-too-high level.

The full study was published in the journal BMJ.