Napping increases memory 5 times? How is afternoon nap good for health?

Some studies have shown that napping improves memory and reduces the risk of heart disease, but there is also research showing that napping increases the risk of disease. Actually the problem is related to how long you sleep. So how long should a healthy nap be?

Article by sports medicine physician Gabe Mirkin, representing the author's own views

Napping from 10 minutes to 2 hours is healthy and can protect memory and other brain functions, as long as you don't sleep too much at night (no more than 8 hours in total). (Photo: Shuterstock)

The study, published in the journal Heart, followed 3,462 people between the ages of 35 and 75 for five years. The results found that people who nap once or twice a week had a much lower risk of heart disease, while those who nap more than twice a week had the same risk of heart disease as those who didn't. nap.

They explain this strange result: People who have a habit of napping are often older, male, smokers and obese, who are inherently at higher risk of heart disease. These people also often sleep longer at night.

When they removed these people at high risk of heart attack from the data, those who slept more than 2 times per week did not have an increased risk of heart attack.

Can napping reduce heart disease risk?

The frequency of naps increases with age, with up to 70% of older adults worldwide napping. A review of scientific studies around the world finds great disagreement about whether napping is healthy or harmful. The Journal of the American Medical Association (JAMA) summarizes the various studies that suggest napping habits:

• Less likely to die of a heart attack
• Increased risk of dying from a heart attack
• Just as likely to have a heart attack as people who don't take a nap

Almost all of the studies on napping and heart attack risk are observational, comparing people who nap with those who don't. This type of study may show an association, but they don't show a cause-and-effect relationship.

How sleep improves brain function

When you've just fallen asleep, your eyes are still, which is called Non-Rapid Eye Movement (NREM) sleep. Then your eyes begin to move rapidly from side to side, which is called Rapid Eye Movement (REM) sleep.

During sleep, you move back and forth between REM and NREM sleep. REM sleep helps restore memory and other brain functions. REM sleep is markedly increased after staying awake for many hours and after exercise.

When you sleep, the nerves in the brain regenerate, as evidenced by increased cell division, synthesis of new proteins, and the removal of breakdown waste from brain metabolism. There is evidence that you learn most of your new knowledge while awake, but you process that knowledge and learn to make better use of it right after you wake up. When you miss your normal sleep time, you partially lose your ability to recall and remember things. I learned this in 7th grade, when I found that I could remember things better when I woke up from a nap. Since then, I always take a nap before reading and writing.

How to take a nap to improve memory?

In a study at the University of Saarland in Germany, a nap of 45 to 60 minutes improved single word memory by fivefold. These results are supported by sleep brainwave changes during EEG brainwave tests, suggesting that memory improves for the better. A 10-minute nap can restore memory and alertness.

In general, people who nap for more than 2 hours a day may experience memory loss known as cognitive decline, while those who nap less than 2 hours a day will have improved memory. 

Napping can have the side effect of interfering with normal nighttime sleep. Therefore, the best nap time for memory is after lunch, between noon and 3 pm.

How to take a nap to benefit the body?

In general, napping is very good for health, but there are people who need more sleep because of heart and brain damage. Too much sleep is often a sign of serious heart and brain disease.

My suggestion is:

• Napping from 10 minutes to 2 hours is healthy and can protect memory and other brain functions, as long as you don't sleep too much at night (no more than 8 hours in total).
• The most memory-friendly nap time is after lunch.
• If you find that in addition to sleeping more than 6 hours at night, you regularly nap for more than 2 hours during the day, you may need to get tested to see if you have a medical condition that is damaging your brain or body. which not.
• Take a 1-2 hour nap after intense exercise to help your brain and muscles recover faster.
• Some studies show that you'll be better at performing thought processing and remembering after you wake up from a nap, or in the morning after a good night's sleep.

Post author: 

Sports medicine doctor, fitness expert and longtime radio host Gabe Mirkin brings you news and advice for healthy living. Dr. Mirkin is a graduate of Harvard University and Baylor College of Medicine, a physician with more than 50 years of experience and a radio talk show host for 25 years. He is one of the very few doctors who is board-certified in four specialties: Sports Medicine, Allergy and Immunology, Pediatrics, and Pediatric Immunology.