Benefits of napping: Research finds an afternoon nap can boost brain  function, but it's about timing

All human beings need sleep to function properly. As we’ve evolved to be active during the day, our sleeping hours are usually during nighttime. Yet cultures around the world also practice some form of a midday nap.

Sometimes, this practice is a recent byproduct of the stress of modern living. The Japanese, with a work culture renowned for pushing people to exhaustion, practice napping at every opportunity. American companies, always seeking a productivity edge, have begun to discover the benefits of power napping.

But older practices favor midday naps longer than 30 minutes. Spain is the most famous example, with their well-known tradition of closing businesses for several hours in the afternoon for a siesta. In Italy, a similar practice is called “riposo.”

Is a longer midday nap a waste of time, hovering close to slothful indulgence? Or are there benefits we might be missing?

Modern failures of sleeping

It’s common knowledge that eight hours per day is the recommended amount of sleep. Yet, in everyone’s personal experience, maintaining that ideal on a daily basis almost never happens.

People are too busy with work or social commitments. Those who are blissfully unencumbered by such obligations might have other diversions: social media, video games, or binge watching. The world just throws too much stress in our direction and inundates us with stimuli. Our Stone Age biology hasn’t evolved a commensurate response.

Sleep studies indicate that even accounting for individual variations in the amount of sleep needed, we tend to get far less than that. 1 in 3 Americans sleep less than seven hours a day.

And the adverse effects kick in with compound interest. Six hours of sleep per night might not seem bad. But if kept up for 10 days straight, your performance will be as bad as someone who hasn’t slept at all for two full days.

On top of that, we’re not good at estimating how much sleep we really get. Again, this gets worse the more sleep-deprived you are. Those who report sleeping 7 hours a night overestimate this by 0.8 hours, for instance.

Small wonder, then, that attention is belatedly being called to this global health epidemic of insufficient sleep.

A complex web of effects

Part of the problem is that our collective attitudes toward sleeping are fairly cavalier. Most people don’t really possess an in-depth understanding of sleep-related benefits. And they don’t appreciate how bad things can get when you’re sleep-deprived.

The metaphors we use don’t help, either. We compare sleep to recharging batteries, with the implication that you can plug in anytime and get enough juice to keep going.

The truth is that sleep plays a significant role in hormone regulation and circadian rhythmicity. These are the mechanisms that essentially enable you to function as an organism, down to the organ and cellular levels. And they interact in a feedback loop.

If you sleep well, your hormonal balance improves, and your body produces more melatonin to make those sleep and circadian rhythms more robust. Disrupt that loop, and your sleep worsens, your hormonal secretion drops, your rhythms go out of whack. Long-term, you may suffer symptoms of thyroid disorder or abnormal metabolism leading to obesity and diabetes.

That’s on top of all the other negative effects of sleep deprivation you can expect to face in the short term.

Making space for longer naps

So if you think you can shave an hour or two off your evening rest to watch another episode of TV, think again. If your boss expects you to work late, report early the next day, and just take a power nap to restore your productivity level, reconsider your job. Are those things worth the cost in the long haul?

It’s not so simple. You can make the case that everyone should be able to cut down on frivolous leisure in favor of better sleep. But when it comes to work, not many employers are willing to ease the pressure.

In fact, the rising popularity of power naps may be viewed as the only solution employees would need. Science tells us that it’s not enough, though. A power nap provides only momentary respite from the effects of sleep deprivation.

So-called “polyphasic sleep,” or staggering your 8 hours across the day, can work if you also ensure that you go through each sleep cycle. That can only happen if your sleep periods are at least 90 minutes long.

Thus, a better compromise for a busy modern lifestyle would involve six or seven hours’ slumber at night, a power nap, and a longer siesta. It’s time to make room for that midday nap of at least an hour and a half in your daily schedule.