Are you feeling a little guilty about your daily, mid-afternoon snooze? Don’t. Research shows that catching a few ZZZs after lunch can be good for your brain. But keep in mind that the length of your nap matters.
While a 30- to 90-minute nap in older adults appears to have brain benefits, anything longer than an hour and a half may create problems with cognition, the ability to think and form memories, according to the study published in the Journal of the American Geriatrics Society.
“I consider napping to be a good thing, but it needs to be taken in the context of the person and his or her own sleep cycles and body,” says Charlene Gamaldo, M.D., medical director of Johns Hopkins Sleep Disorders Center. For older people, as the study showed, longer naps tend to interfere with cognition, she says.
Napping for a Better Brain
Researchers looked at data from 2,974 people in China ages 65 and older. Nearly 60 percent of participants reported napping after lunch for about an hour.
Scientists found that people who napped for 30 to 90 minutes had better word recall – which is a sign of good memory – than people who did not nap or who napped for longer than 90 minutes. People who napped for that golden 30 to 90 minutes were also better at figure drawing, another sign of good cognition.
One theory explaining poor cognition in those who take longer naps: Resting more during the day may be a sign of poor quality nighttime sleep, according to Gamaldo. “In the study, naps longer than 90 minutes could have been called ‘a second sleep.’” This poor quality nighttime sleep – the kind that requires extra-long napping during the day – can lead to cognitive problems, she adds.
More Problems with Longer Naps
Longer naps can pose a couple of other problems, says Gamaldo, including:
1. Temporary grogginess: People who take longer naps may feel groggy immediately after they wake up, says Gamaldo. “Because they are sleeping longer, they may wake up from a deeper stage of sleep, which occurs later in the cycle, and feel fuzzy headed,” she says.
2. Inability to sleep at night: Gamaldo has seen patients who take long naps during the day have insomnia at night. “You might want to think about limiting your napping if you’re having problems with insomnia, or it’s taking you more than 30 minutes to fall asleep at bedtime.”
A Fine Balance
Overall, studies show that people who sleep too much or too little may have poor health and even a shorter life span. Consequently, “people need to get the right quantity and quality of rest,” says Gamaldo.