Can napping make your brain bigger? Yes, says a recent study from researchers at University College London, published in the medical journal Sleep Health. Looking at nearly 400,000 people ages 40 to 69, they found that those who regularly took short daytime naps had larger brains—a biomarker of good brain health and a lower risk of dementia.
In another study, published in the European Journal of Internal Medicine, researchers found that people with high blood pressure—the No. 1 risk factor for heart attack and stroke—had significantly lower blood pressure if they napped. The effect was as powerful as other lifestyle changes, like eating a diet rich in whole foods and exercising regularly. How can something as simple as a nap be so good for your brain and body?
Humans are the only animals that try to get all their sleep in one bout, a sleep pattern called monophasic. All other animals are polyphasic, getting their sleep in small bouts. Cats, for example, sleep in periods of 80 minutes (the famous “cat nap”), totaling up to 13 hours of sleep per day.
Our monophasic sleep habits are the result of culture not nature. It’s a pattern humans have devised to maximize productivity during the day. But monophasic sleep is not necessarily the best pattern for health and well-being—or even productivity.
For many people, the most natural sleep pattern is biphasic—a long period of sleep at night and a shorter period of sleep during the day. This allows the mind-body system to regularly enter the “downstate”—a restorative time when the system gets to quiet down and be less active.
There are many refreshing physiological changes that occur during downstates of sleeping and napping. Brain and body temperature drop. Electrical activity in the brain slows down. Specific areas in the brain begin to take it easy, from the heart-regulating brainstem to the problem-solving prefrontal cortex. Breathing becomes shallower. The body stops producing tissue-damaging stress hormones and starts producing tissue-repairing growth hormones.
Entering the downstate of napping can produce many benefits in mind and body:
Increased alertness. For many, this is the most important benefit of napping—whether you’re driving, working, studying, or on vacation. NASA studies have demonstrated that alertness increases by as much as 100 percent after a brief nap. Studies also show that a nap during or after work allows you to be as alert and ready for the second part of your day as if it were a brand-new day.
Deeper sleep. Sleeping during the day helps you sleep better at night. Doctors have even begun recommending treatment of syndromes like excessive daytime sleepiness and narcolepsy (sudden, uncontrollable episodes of sleep during the day) with a structured program of naps. Naps also supplement sleep, increasing your total sleep time.
Stronger memory. Brain changes during sleep—at night and during a nap—consolidate memories, making them stronger. Your short- and long-term memory are improved. You’re more able to form a habit or develop a skill. And you’re less likely to be bothered by unproductive snippets of useless memories.
Balanced emotions. During nighttime sleep and napping, the brain processes emotions. As a result, your mood is better. You feel less frustrated. You’re more emotionally resilient, better able to handle situations that would otherwise feel distressing or threatening.
Greater creativity. Consolidating memory and processing emotions improves creativity because if you don’t deal effectively with old information, you can’t effectively produce new information. A study published in the Proceedings of the National Academy of Sciences showed that longer naps, which get you through a whole sleep cycle (approximately 90 minutes), improve creativity by 40 percent compared with periods of quiet rest or shorter naps.
Faster performance. All of us engage in tasks that involve coordination, whether we’re typing, operating machinery, or bagging groceries. A Harvard study demonstrated that the speed of a learned motor performance is the same after a nap as after a full night’s sleep.
Faster recovery. Naps help athletes recover faster from intense training, and they can help you recover from any type of demanding physical or mental performance.
Better decisions. Pilots who are allowed to nap in the cockpit commit fewer judgment errors on takeoff and landings than those who aren’t.
Improved perception. Research shows that a nap can be as effective as a night of sleep in improving perceptual skills—for driving, cooking, appreciating music or art, reading, proofreading, and bird-watching.
Working smarter and harder. Businesses that allow their employees to nap have shown decreases in errors and increases in productivity.
Energized sex life. Sleep deprivation dampens sex drive and sexual function. Napping reverses those effects.
Weight loss. Sleepy people reach for high-fat, sugar-rich foods more than people who are rested. Taking a nap also helps you produce more growth hormone, which reduces body fat.
Diabetes defense. Sleep deprivation increases the risk for type 2 diabetes. Napping after meals builds up your defense against diabetes while improving the way you process sugars.
Let’s start with a surprising statement: Naps aren’t for everyone! If you wake up after a nap and feel great, napping is for you. If you wake up after a nap and don’t feel great, you may not derive any benefit from regular napping. There is no universal formula for napping: It’s a personal preference. That said, if you like to nap and want to nap, there are several ways to optimize the experience.
“We were not made by nature to work, or even to play, from eight o’clock in the morning till midnight,” he famously said. “We ought to break our days and our marches into two.”
In China, children grow up napping at their desk at school, and continue the habit through college and even at some workplaces. Try to nap in the same place with the same routine. Whatever works for you, do that every time.
Plan for a nap at work. Some work environments are nap-positive and may even have a nap room. But what if your workplace doesn’t accommodate napping? Consider napping in your car, if the temperature in the car isn’t too hot or cold. In temperate weather, it’s possible to nap in a park. Or you might go to the library and take a brief nap in a comfortable chair. Wherever you go, set a gentle alarm to make sure you wake up on time. Good times to nap at work are at the end of your lunch break or during your afternoon break.
