Naps could be raising blood pressure and risk of stroke

We’ve all experienced the occasional sleepless night. Maybe you’ve got a big day ahead and it’s weighing on you, or maybe you’re thrust into a high-stakes drug bust turned kidnapping like the main character in the appropriately named Sleepless Night.

Whatever the reason, sometimes a nap is a good way to wind down from a stressful day or recover from a late night saving your kid from criminals, but they may be doing you more harm than good. It turns out, frequent daytime napping has been associated with a higher-than-normal risk of increased blood pressure and risk of stroke, according to a new paper published in the journal Hypertension.

Scientists from Central South University took data from the U.K. Biobank, a biomedical database which houses lifestyle and health information from 500,000 anonymous participants, gathered between 2006 and 2010. Participants provided biological samples as well as behavioral information including how frequently they napped during the day.

Researchers excluded those individuals who already had a history of high blood pressure or stroke, reducing their sample size to approximately 360,000 individuals. They then looked at those individuals who reported regular napping during the daytime and the prevalence of high blood pressure or stroke down the line, with an average follow up of 11 years.

The commonsense conclusion is that people who nap more often might be more relaxed and thus be at a reduced risk for these conditions. After all, stress is an indicator for both high blood pressure and stroke risk, and it’s hard to be stressed when you’re curled up on the couch. However, the results of the team’s analysis reached the opposite conclusion.

Frequent nappers were 12% more likely to develop high blood pressure and 24% more likely to have a stroke later in life. Those numbers had some fluidity, with younger individuals having a higher lifetime risk than those who were older. Additionally, a change in behavior from never napping to sometimes or usually napping was also associated with increased health risks.

The precise mechanism behind the association isn’t yet clear and it’s possible that the naps themselves aren’t actually the culprit. Instead, they might be another symptom of an underlying cause. Researchers indicated that frequent napping might be caused by poor sleep during the night. Naps, while helpful and relaxing, may not be enough to make up for poor nighttime sleeping and that might be the ultimate cause of health concerns later in life.

Frequent napping was also most commonly found in men who reported regular tobacco and alcohol use as well as insomnia and snoring, all of which might have an impact on heart health. There might also be a genetic component. The study found that napping frequency was associated with a genetic predisposition for higher blood pressure. As with most things regarding our health, there are a lot of pieces all working together and no single component is likely to blame all on its own.

That said, if you find yourself craving a nap during the daytime more often than not, it might work taking inventory of your lifestyle to determine how you can adjust your sleep hygiene and stay conscious throughout the day. A nap is nice. A dirt nap, not so much.