You snooze, you win: Study links naps, health
WASHINGTON – The next time the boss finds you snoozing at your desk, take heart – literally.
A large new study has found that people who regularly took a siesta were significantly less likely to die from heart disease.
“Taking a nap could turn out to be an important weapon in the fight against coronary mortality,” said Dimitrios Trichopoulos of the Harvard School of Public Health in Boston, who led the study published Monday in the Archives of Internal Medicine.
The study of more than 23,000 Greek adults – the biggest and best investigation of the subject to date – found that those who regularly took a midday siesta were more than 30 percent less likely to die from heart disease.
Other experts said the results were intriguing. Heart disease claims more than 650,000 Americans each year, making it the United States’ No. 1 cause of death.
“It’s interesting. A little siesta, a little snooze may be beneficial,” said Gerald Fletcher, a cardiologist at the Mayo Clinic in Jacksonville, Fla., speaking on behalf of the American Heart Association. “It’s simple, but it has a lot of promise.”
While more research is needed to confirm and explore the findings, there are several ways that napping could reduce the risk for heart attacks, experts said.
“Napping may help deal with the stress of daily living,” said Michael Twery, who directs the National Heart Lung and Blood Institute’s National Center for Sleep Disorders Research. “Another possibility is that it is part of the normal biological rhythm of daily living. The biological clock that drives sleep and wakefulness has two cycles each day, and one of them dips usually in the early afternoon. It’s possible that not engaging in napping for some people might disrupt these processes.”
Researchers have long known that countries like Greece, Italy and Spain, where people commonly take siestas, have lower heart disease rates than would be expected. But previous studies that attempted to assess the relationship between naps and heart disease have produced mixed results. The new study is the first to try to fully account for factors that might confuse the findings, such as physical activity, diet and other illnesses.
“This study has a number of advantages,” Trichopoulos said.
Trichopoulos and colleagues at the University of Athens studied 23,681 Greek men and women ages 20 to 86 who had no history of heart disease or any other serious health problem when they enrolled in the study between 1994 and 1999. The researchers asked the participants whether they took midday naps and, if so, how often and for how long. They also asked detailed questions about their health and lifestyles, such as whether they had any illnesses that might make them sleep more, how much exercise they got and what they ate.
After an average of more than six years of follow-up, 792 of the study subjects died, 133 of them from heart disease. After the researchers took into account factors that could confuse the issue, they found that those who took naps frequently were 34 percent less likely to die from heart disease than those who did not. The biggest nappers – 79 people who took a siesta for 30 minutes or more at least three times a week – had a 37 percent lower risk.
While it is too soon to recommend naps to prevent heart disease, Trichopoulos said that the finding offers one more reason to nap.
“If you have an opportunity to take a nap, then, yes, do it,” he said. “If you’re accustomed to taking a nap, then don’t give it up.”