Napping tied to 5 mm Hg drop in systolic blood pressure

A napping habit could lower blood pressure to a similar extent as other lifestyle modifications and some drugs, according to research scheduled to be presented March 18 at the American College of Cardiology’s scientific sessions in New Orleans.

Researchers studied 212 people who were 62 years old on average and had a mean systolic blood pressure (SBP) of 129.9 mm Hg. Compared to those who didn’t nap, participants who took a daytime snooze had average 24-hour SBPs 5.3 mm Hg lower (127.6 mm Hg vs. 132.9 mm Hg). For each hour of napping—the average duration was 49 minutes—SBP was lowered by about 3 mm Hg.

“These findings are important because a drop in blood pressure as small as 2 mm Hg can reduce the risk of cardiovascular events such as heart attack by up to 10 percent,” study co-author Manolis Kallistratos, MD, with Asklepieion General Hospital in Voula, Greece, said in a press release. “Based on our findings, if someone has the luxury to take a nap during the day, it may also have benefits for high blood pressure. Napping can be easily adopted and typically doesn’t cost anything.”

Kallistratos said curbing salt and alcohol intake typically reduces SBP levels by 3 to 5 mm Hg, a similar magnitude as the associations observed with napping. Low-dose antihypertensive medication usually lowers SBP by 5 to 7 mm Hg.

The nappers in the study were taking a similar amount of medications, on average, as non-nappers. They also shared an equal burden of risk factors, other than there being more smokers in the napping group.

In addition, the groups had similar rates of blood pressure drops at night, suggesting reductions in ambulatory daytime readings would more likely be due to midday naps.

“We obviously don't want to encourage people to sleep for hours on end during the day, but on the other hand, they shouldn’t feel guilty if they can take a short nap, given the potential health benefits,” Kallistratos said. “Even though both groups were receiving the same number of medications and blood pressure was well controlled, there was still a significant decrease in blood pressure among those who slept during midday.” 

Kallistratos et al. said regional considerations must be weighed when interpreting the findings. Both the Mediterranean diet and daytime napping are popular in the study region, which may have contributed to an overall healthier profile among participants than would be seen in other areas of the world.

The Mediterranean diet was named the No. 1 overall diet and tied for the most heart-healthy diet for 2019 in rankings compiled by U.S. News and World Report.