Turns out, the perfect power nap requires more than a peaceful daytime sleep—how long you're napping for and when makes a huge difference for your health
[the best nap length sleep] Your naps could be wrecking your wellbeing: People who napped for 60 minutes or more per day had a 46 percent increased risk of developing type 2 diabetes, whereas shorter naps—an hour or less per day—didn't increase their risk of the disease, according to a recent study presented at the annual meeting of the European Association for the Study of Diabetes.
Unfortunately, this isn't the only study to I.D. a link between long naps and health hazards. Research has found that spending lots of time in Z-land during the day is associated with an increase risk of heart disease, metabolic syndrome, liver disease, and even death.
The issue affecting your health may lie in the reason you feel so sleepy during the day, says W. Christopher Winter, M.D., a neurologist and sleep medicine physician at Charlottesville Neurology and Sleep Medicine in Virginia. For instance, sleep apnea—in which you stop breathing for several seconds at a time up to hundreds of times per night—can affect the quality and quantity of your sleep. The condition can boost your risk for a slew of health issues including obesity, diabetes, heart disease, stroke, and more. In addition, getting into a habit of taking long naps during the day may affect your ability to sleep well at night, so you can get into a cycle where you're chronically sleep deprived, which has also been shown to take a toll on your health, he adds.
So what's the ideal length for a nap? Winter recommends limiting daytime sleep to 20 to 25 minutes and scheduling it for earlier in the day, before 1 p.m. "At that time it adds to the previous night's sleep rather than subtracting from the sleep you're going to get that night," he says. And the 20 to 25-minute threshold prevents you from getting into the deeper stages of sleep, which can leave you feeling groggy instead of energized when you wake. "Think about naps more like a snack than a meal," he says.
If you regularly feel so sleepy during the day that a 20-minute siesta isn't enough to put some pep in your step, then make an appointment with your doc. You may have a more serious issue affecting your sleep at night that could be putting your health on the line, Winter says.