For a long time, we’ve known that not getting enough sleep can derail your health and increase your risk of diabetes, obesity, depression, immune problems, and other health problems.

But now, researchers have uncovered another bedtime habit that can lead to dangerous problems with your heart. I’m talking about going to bed at the wrong time. Here’s what you need to know…

Deciding when to climb into bed might seem like a minor matter. However, a study in England found that if you lay your head down on the pillow at the right time, you can dramatically reduce your risk of heart disease.

According to a study at the University of Exeter in England, people who go to bed between the hours of 10 and 11 pm ran a significantly lower risk of heart disease than people who go to bed later or earlier than that time.1

Your Heart’s Daily Rhythm

Researcher David Plans, PhD, explains, saying, “The body has a 24-hour internal clock, called circadian rhythm, that helps regulate physical and mental functioning. While we cannot conclude causation from our study, the results suggest that early or late bedtimes may be more likely to disrupt the body clock, with adverse consequences for cardiovascular health.”

Previously, other studies have shown that getting too little sleep can compromise heart health, but few studies have looked at the effects of the times that people get to sleep.

“Our study indicates that the optimum time to go to sleep is at a specific point in the body’s 24-hour cycle and deviations may be detrimental to health,” says professor Plans. “The riskiest time was after midnight, potentially because it may reduce the likelihood of seeing morning light, which resets the body clock.”

The Graveyard Shift Can be Dangerous

Along with the risk attached to going to bed too late or too early, another study shows that staying up all night – working the night shift – also disrupts the circadian rhythm and interferes with heart function.

A study out of Tulane, coordinated with other institutions, shows that working the night shift is associated with having an irregular and seriously accelerated heart rhythm – a condition known as atrial fibrillation (AFib).2

Researcher Yingli Lu, M.D., PhD, says, “Our findings have public health implications for preventing atrial fibrillation. They suggest that reducing both the frequency and the duration of night shift work may be beneficial for the health of the heart and blood vessels.”

The study looked at the work habits and heart health of more than 280,000 people. It showed that consistently working the night shift increases the risk of AFib by 12 percent compared to people who work during normal daytime hours. That risk increases to 18 percent after ten years of night shift work.

Among people who alternate between day and night shifts, the study shows that if you work three to eight night shifts a month for ten or more years, your risk for AFib increases by 22 percent (the extra stress of continually changing your daily routine adds to the chances of a heart problem).

In the research, women were in more heart danger than men. In fact, their risk of AFib climbed by a whopping 64 percent after working a night shift for more than ten years.

Keeping Your Heart on a Steady, Healthier Course

The research shows that an important way to preserve the health of your heart is to go to bed between 10 and 11pm and to avoid working a job that demands you stay up all night.

Getting more exercise can also help. The Tulane researchers found that there was less AFib among people who got either 150 minutes of moderate exercise weekly or 75 minutes of intense exercise every week. (Alternatively, some combination of the two was also protective).

In my opinion, the advice is clear and relatively simple: Get to bed at a reasonable hour and get plenty of exercise. Doing these two things will give you a better chance of avoiding heart disease and the deadly conditions that go with it.


  1. https://academic.oup.com/eurheartj/article/42/40/4180/6347324 
  2. https://academic.oup.com/eurheartj/article/42/40/4180/6347324