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8 Scientific Benefits of Napping

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Even on the best of days, life can be exhausting. If you find your energy flagging in the middle of the day, you might like to know that 34 percent of Americans nap. Napping is a healthy way to restore the deficits of sleep deprivation. Whether you bow down to the ritual of a mid-afternoon siesta or never stop to snooze, you may think twice about the power of napping after reading about these eight benefits.

1. NAPPING CAN BOOST YOUR IMMUNE SYSTEM.

Sleep deprivation—particularly repeated, chronic lack of sleep—takes a toll on your neuroendocrine and immune functions by increasing inflammatory molecules known as cytokines, as well as stress hormones like cortisol and norepinephrine. A 2015 study in the Journal of Clinical Endocrinology & Metabolism took 11 healthy young men and restricted them to a night of only two hours of sleep. Blood and urine tests measured higher cytokines and levels of norepinephrine in both groups after sleep deprivation. The following day, one group was given two half-hour naps, while the control group did not have any naps. Blood and urine samples of those who napped showed that their cytokines and norepinephrine levels had returned to normal, as though they had never lost a night of sleep.

2. A NAP CAN IMPROVE NIGHT ALERTNESS.

For people who work at night, or through the night, several studies have shown that naps from between 30 minutes to four hours long that are taken in advance of the shift—what's known as a "prophylactic nap"—improve performance and alertness. These naps can also improve nighttime driving alertness on the way home from the shift. However, most of these studies also include the administration of caffeine, which likely contributed. Yet a 1995 study in Sleep, which compared naps and caffeine, found that "naps, in general, provided longer and less graded changes in performance, mood and alertness than did caffeine, which displayed peak effectiveness and loss of effect within about six hours."

3. NAPS + CAFFEINE ARE A ONE-TWO PUNCH AGAINST SLEEPINESS. ASK SURGEONS.

Surgeons must often perform continuous surgery for hours longer than the average person would ever have to persist at a task. A 1994 study in the journal Ergonomics found that naps were indeed effective at keeping surgeons who had to remain awake for 24 hours alert, but only when caffeine was administered, too. Neither naps or caffeine alone were sufficient.

4. TO IMPROVE DAYTIME ALERTNESS, TAKE FREQUENT NAPS.

Daytime napping also appears to improve mental alertness and performance, according to a number of laboratory studies. However, researchers found that shorter naps were more effective than longer ones. The most effective time of them all was 10 minutes, which produced the best outcomes in all sleep measures including "subjective sleepiness, fatigue, vigor, and cognitive performance." A 30-minute nap could produce the same effects but brought about "a period of impaired alertness."

5. NAPS HELP YOU LEARN NEW SKILLS.

If you want to get better at learning a new skill, you might want to take more frequent naps. A 2006 study in Biological Physiology broke participants into two groups: those who napped frequently and those who napped sporadically. Each group was given a nap before a reading task. Habitual nappers—people who reported napping frequently—did better on the reading and retention task. Researchers determined that the brains of habitual nappers consolidated motor learning better, which is part of the process of learning a new skill.

6. IMPROVE YOUR PHYSICAL STAMINA WITH NAPPING.

It turns out that napping is not only just good for mental processes, but has a positive impact on physical stamina and performance as well. A 2007 study in the Journal of Sports Sciences put 10 healthy men through a series of sprints before and after a 30-minute, post-lunch nap. Sprint times improved after the naps, suggesting to the researchers that a post-lunch nap "improves alertness and aspects of mental and physical performance following partial sleep loss." They suggest that napping may be an important part of athletes’ regimens who are undergoing restricted sleep during training or competition.

7. NAP TO IMPROVE YOUR MEMORY.

One of the many functions of regular night time sleep is to consolidate memory. A 2010 study in Neurobiology of Learning and Memory set out to see whether daytime naps also improve memory processes, particularly associative memory (the ability to make connects between unrelated objects). Thirty-one healthy participants were given a learning task at 12 p.m. to memorize two sets of face-object photograph pairs. The objects in each pair occurred in both sets but were paired with different faces. Participants were broken into two groups: those who had a 90-minute daytime nap or those who did not. At 4:30 p.m., participants who napped showed notably better retention of associative memory.

8. A 90-MINUTE NAP IS AS GOOD AS A FULL NIGHT’S SLEEP FOR PERCEPTUAL LEARNING.

Previous research demonstrated that people perform better on a visual texture-distinguishing task after a night of sleep than they do immediately after learning it. A 2003 study in Nature Neuroscience found that people performed just as well on the test after a 60- to 90-minute nap as they did after a full night of slumber.

"What's amazing is that in a 90-minute nap, you can get the same [learning] benefits as an eight-hour sleep period," lead author Sarah Mednick said in an interview with the American Psychological Association. "The nap is having an additive benefit on top of a good night of sleep."

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Why You Should Think Twice About Drinking From Ceramics You Made by Hand
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Ceramic ware is much safer than it used to be (Fiesta ware hasn’t coated its plates in uranium since 1973), but according to NPR, not all new ceramics are free of dangerous chemicals. If you own a mug, bowl, plate, or other ceramic kitchen item that was glazed before entering the kiln, it may contain trace amounts of harmful lead.

Earthenware is often coated with a shiny, ceramic glaze. If the clay used to sculpt the vessel is nontoxic, that doesn’t necessarily mean the glaze is. Historically, the chemical has been used in glazes to give pottery a glossy finish and brighten colors like orange, yellow, and red.

Sometimes the amount of lead in a product is minuscule, but even trace amounts can contaminate whatever you're eating or drinking. Over time, exposure to lead in small doses can lead to heightened blood pressure, lowered kidney function, and reproductive issues. Lead can cause even more serious problems in kids, including slowed physical and mental development.

As the dangers of even small amounts of lead have become more widely known, the ceramics industry has gradually eliminated the additive from its products. Most of the big-name commercial ceramic brands, like Crock-Pot and Fiesta ware, have cut it out all together. But there are still some manufacturers, especially abroad, that still use it. Luckily, the FDA keeps a list of the ceramic ware it tests that has been shown to contain lead.

Beyond that list, there’s another group of products consumers should be wary of: kiln-baked dishware that you either bought from an independent artist or made yourself. The ceramic mug you crafted at your local pottery studio isn’t subject to FDA regulations, and therefore it may be better suited to looking pretty on your shelf than to holding beverages. This is especially true when consuming something acidic, like coffee, which can cause any lead hiding in the glaze to leach out.

If you’re not ready to retire your hand-crafted ceramic plates, the FDA offers one possible solution: Purchase a home lead testing kit and analyze the items yourself. If the tests come back negative, your homemade dishware can keep its spot on your dinner table.

[h/t NPR]

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Marathon Running Won't Undo Poor Lifestyle Choices, Study Suggests
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Even marathon participants can't outrun an unhealthy lifestyle, according to a new study highlighted by The New York Times.

For years, expert opinion has been mixed on whether long-distance running helps or hurts hearts. In the 1970s, research suggested that marathon running and a heart-healthy diet would completely prevent atherosclerosis (a buildup of harmful plaque in the arteries). But since high-profile runners have died of heart attacks, scientists in the 1980s began to worry that running might actually harm the vital organ. Compounding this fear in recent years were studies suggesting that male endurance athletes exhibited more signs of heart scarring or plaques than their less-active counterparts.

Experts don't have a verdict quite yet, but researchers from the University of Minnesota and Stanford and their colleagues have some good news—running doesn't seem to harm athletes' hearts, but it's also not a panacea for heart disease. They figured this out by asking 50 longtime marathon runners, all male, with an average age of 59, to fill out questionnaires about their training, health history, and habits, and then examining them for signs of atherosclerosis.

Only 16 of the runners ended up having no plaque in their arteries, and the rest exhibited slight, moderate, or worrisome amounts. The men who had unhealthy hearts also had a history of smoking and high cholesterol. A grueling training regime seemed to have no effect on these levels.

Bottom line? Marathon running won't hurt your heart, but it's not a magic bullet for poor lifestyle choices.

[h/t The New York Times]

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