Breakthrough research shows that napping confers significant health benefits

If you’re like most Americans, you probably consider napping an indulgence.

What you may not realize: Napping is widely known to sharpen mental fitness (including memory), and it also confers significant overall health benefits.

Important finding: When researchers from the Harvard School of Public Health and the University of Athens Medical School recently followed about 23,000 healthy Greek adults (average age 53), they found that study participants who napped at least 30 minutes three times a week or more were 37% less likely to die from heart disease and stroke over a six-year period.

How to get the greatest health benefits from napping…

IT’S TIME TO NAP!

Humans are biologically programmed to nap. Our bodies experience a slight drop in physiological processes such as body temperature, blood pressure and the secretion of digestive juices (at around 2 pm for people who awaken at 8 am) — similar to the larger dips that occur at night. These drops signal the body that it’s time to sleep.

There’s strong scientific evidence showing that people who nap are more alert, make better decisions, score significantly higher on creativity and memory tests and have better motor function after napping compared with people who don’t nap.

Surprising fact: Despite the popular notion that lunch makes people sleepy due to the digestion process, research shows that it’s actually the body’s temperature drop that is responsible. This temperature drop occurs whether or not you eat lunch.

Why napping provides so many benefits: Napping just 20 minutes is enough time for restorative processes that occur during sleep to take place.

THE RIGHT — AND WRONG — WAY TO NAP

Here are my five secrets for getting the most from your naps — and some common mistakes to avoid…

SECRET 1. Make a 20-minute nap part of your daily routine, like exercising and brushing your teeth.

Common mistake: Squeezing in a nap whenever you can.

My recommendation: Take a nap at the same time every day (even if you don’t feel sleepy) so that your body adjusts to falling asleep then. Because most Americans have trained themselves to not nap, the instinct needs to be relearned.

The ideal time to take a nap from a biorhythm standpoint is six hours after awakening for the day.

Example: If you usually wake up at 7 am, your best napping time will be around 1 pm.

Of course, your exact nap time may depend on your daily activities. Just don’t nap within three hours of your bedtime.

SECRET 2. Choose a comfortable, quiet place where you won’t be disturbed.

Common mistake: Napping in your living area at home or in an office at work. Even if you’re not disturbed by noise or other interruptions, you will still feel the emotional tug of your daily activities.

My recommendation: Go to a place unrelated to daytime tasks, such as your bedroom, an empty conference room, a park or your car with the seat reclined and the window slightly cracked so that you get some fresh air.

Also, try earplugs if you have trouble drifting off to sleep. Or consider using a white-noise machine to block out distracting sounds.

New option: The Apple iPhone White Noise App is very effective at blocking out noise.

SECRET 3. Cover yourself with a light blanket or jacket, if possible. This will make you more comfortable because your body temperature is lower than usual while napping.

Common mistake: Many people think that they need to be in a darkened room to nap. This may not be true. Research being conducted at the University of California, San Diego’s sleep laboratory has found no effect from different levels of light on a person’s ability to nap.

Possible reason: Since napping appears to be programmed into us, we may have evolved to fall asleep for brief periods during daylight without a need for melatonin, the sleep hormone that the body produces only in darkness.

SECRET 4. Set an alarm to go off after 20 minutes. Use whatever is most convenient — an alarm on your watch or cell phone, for example. The Nap App on the Apple iPod functions as an alarm that awakens nappers with a tone or vibration.

Using an alarm will prevent you from napping too long. It also allows you to relax, because you won’t have to worry about the clock.

Interesting fact: Even when nappers thought they were awake throughout their nap times, researchers’ anecdotal observations have shown that the nappers usually did dip into light sleep, which can help with alertness and motor performance.

Common mistake: Napping for more than 30 minutes. These longer naps take you from light “Stage 2” sleep into deeper “Stage 3” and “Stage 4” sleep, which are harder to wake up from and will leave you groggy.

My recommendation: If you would like to take a longer nap, make sure that it lasts for 60 to 90 minutes. That’s long enough to move through the deeper sleep stages and return to lighter Stage 2 and rapid-eye movement (REM) sleep — also known as “dreaming sleep.”

This type of longer nap has the added benefit of stimulating the brain regions that integrate newly learned information into your long-term memory.

New finding: In a recent study conducted at the University of California, Berkeley, 39 healthy adults were given a rigorous learning exercise at noon. Half of them then took a 90-minute nap at 2 pm, while the other half didn’t. When doing new exercises at 6 pm, the group that had napped did significantly better than those who did not nap.

SECRET 5. Go back to sleep for five minutes if you feel groggy from over-napping. If you’re groggy, this means that you have moved into the deeper stages of sleep. Going back to sleep for five minutes will allow you to move further out of those sleep stages.

If you find that you’re groggy after a 20-minute nap: Shorten your nap to 10 minutes to avoid progressing into deeper sleep.

WHEN NAPPING MAY MEAN TROUBLE

Even though the bulk of research has found that napping is a healthful practice, one widely publicized study found the opposite — specifically, that older women who take excessive daily naps are more likely to die.

The study subjects (age 69 and older) who died napped the longest (more than three hours daily). They were 44% more likely to die from any cause and 58% more likely to die from cardiovascular causes than those who did not report taking naps.

The details of the research results suggest that the study participants had underlying sleep disorders, such as obstructive sleep apnea (temporary cessation of breathing during sleep) or an illness such as depression or heart disease.

Key fact not widely reported: The same study found that women who napped three hours or less per week had no increased mortality.

In addition, those who slept nine to 10 hours per 24-hour period (overnight sleep plus naps) were at greater risk of dying than those who slept eight to nine hours total in the same time period. Researchers are unsure whether these findings would also apply to men.

My advice: If you’re sleeping excessively at night, consult a sleep doctor, who will place you on a strict sleep schedule that will not include napping.

To find a sleep clinic near you that is accredited by the American Academy of Sleep Medicine, go to www.SleepCenters.org.