Study Links Night Shift Workers to Increased Risk of Heart Disease

An estimated 15 million Americans work some type of rotating night shift. While there are certain perks to working at night, it also comes with its disadvantages, one of which is the negative impact that it has on one's health. According to a recent study, night shift workers have an increased risk of developing heart disease.

Researchers from the Celine Vetter of Brigham and Women's Hospital in Boston found that nurses who worked night shifts for a decade or longer had roughly a 15% greater risk of coronary disease when compared to nurses who worked the day shift. Some people may turn their heads at this study, assuming that other factors are to blame for the increased risk of coronary heart disease. As explained by the study's lead author, however, smoking, poor diet, lack of physical activity and other common health factors were taken into account during this study.

"There are a number of known risk factors for coronary heart disease, such as smoking, poor diet, lack of physical activity, and elevated body mass index," said Celine Vetter of Brigham and Women's Hospital in Boston, the study's lead author. "However, even after controlling for these risk factors, we still saw an increased risk of coronary heart disease associated with rotating shift work."

Researchers came to this conclusion after analyzing data from two existing studies of nurses that have been going on since 1976. During two year intervals, some 300,000 nurses report their health to the team.

So, why do night shift workers have an increased risk of developing coronary heart disease? The study's researchers didn't point to a causation, although there are likely several different factors contributing to the phenomenon. For starters, working night shifts throws off the body's circadian clock, which is used to regulate its day-and-night cycle. When this occurs, metabolism and hormone production can also be distributed, resulting in lower levels of "good" hormones like oxytocin and higher levels of "bad" hormones like cortisol.

But working night shifts does more than just increase your risk of heart disease. Researchers also found that nurses who work night shifts are more likely to gain weight and smoke cigarettes. This, of course, can open up the doors to a whole new world of potential health problems.

The bottom line is that night shifts can take a toll on your body, both mentally and physically. So if you are going to clock hours after the sun sets, put forth the effort to eat right, exercise, and get plenty of sleep.