They Don't Call it a "Power Nap" for Nothing
News flash: Naps are good for guys who are short on sleep. And there’s freshly published research to prove it.
Now, before you call me Captain Obvious, I know what you’re thinking. Going by sound bites alone, this isn’t exactly groundbreaking stuff. Of course a solid nap is going to top off your tank when you’re running on empty. That’s not rocket science. It’s garden variety common sense.
But I want to underscore just how big of an impact a daily nap can make. Because according to a brand new study, it does a lot more than simply offset fatigue.
First, though, a little context: Researchers performed sleep testing on a group of 11 healthy men between the ages of 25 and 32. This included two three-day-long sessions in a controlled laboratory.
Both sessions began with a full eight-hour night’s sleep on the first night. They continued with sleep restricted to two hours on the second night. And they ended with unlimited sleep on the third and final night.
But there was one key difference between the two sessions...
During the first session, the guys were not allowed to nap. During the second session, however, researchers allowed them two 30-minute naps on the final day. (Remember, that was the day following a night of severe sleep restriction.)
And let’s just say they don’t call them “power naps” for nothing...
For one thing, analysis of urine and saliva samples showed a profound effect on hormone levels. Specifically, tests showed that sleep restriction more than doubled levels of norepinephrine — a stress hormone that jacks your heart rate, blood pressure, and blood sugar.
But napping completely reversed this negative effect. And that’s not all...
Those two 30-minute naps also restored depleted supplies of interleukin-6 — an immune protein that plays a critical role in battling infection. In other words, a simple nap may be able to reverse the short-term damage that a bad night’s sleep does to your immune system.
It’s enough to decide your fate against a cold or the flu on any given sleep deprived day. And if that’s not an airtight case for stopping to recharge your batteries instead of powering through, I don’t know what is.
But my enthusiastic nap promotion comes with a few strings attached. And let me tell you why.
Previous research has shown that regular daytime napping can actually raise your risk of mortality. In fact, one study — published in the American Journal of Epidemiology just last year — showed that napping for less than an hour daily was associated with a 15% higher risk of death. And if that nap was an hour or longer, the risk rocketed as high as 32%.2
So what’s going on here? Well, I’m going to go out on a limb and say that it’s not the naps themselves that are lethal. Obviously, this most recent study suggests quite the opposite. And other studies actively support the wisdom of a daytime siesta, too.
Specifically, research shows that short afternoon naps can refresh your mind and boost learning and job performance.3 We’re talking 30 minutes or less, to avoid “sleep inertia” that can make it hard to wake up. And even as little as six minutes — yes, six minutes — may be enough to definitively increase memory retention.4
But if you’re sleeping excessively during the day, it could also mean that an underlying health problem is brewing. (Respiratory diseases had a particularly strong association with heavy napping in the study I mentioned above.) Or it could simply mean that you’re not catching enough quality Zzz’s overnight.
And poor nighttime sleep is a killer, any way you slice it.
I’ve explained the dire risks of chronic sleep deprivation here before. So by now, you should know how essential those seven to eight hours are. But in light of today’s conversation, I want to emphasize that when you sleep appears to be almost as important as how much you sleep.
In fact, one recent study showed that “circadian misalignment” — the technical term for a daysleeping schedule that defies natural biological rhythms — doubles the inflammation and metabolic dysfunction that regular old sleep deprivation delivers.5
That’s a seriously bad influence. And it’s also a major incentive to get your sleep hygiene in check...
So here’s the deal: if you’re able to sleep at night, that’s when you want to do it. If you’re stuck with shift work, try to maintain as normal a schedule as possible, with those solid stretches of sleep as your absolute top priority.
And if you find yourself in a sleep-deprived jam?
Go ahead and grab that afternoon nap when you can. If these most recent findings are any indication, it will save your body from a world of hurt in the short term. But it’s not a substitute for a quality night’s sleep.
Daytime napping may not always be a deal breaker for your health — especially if we’re talking about 10 to 20 minute “power naps” to refresh your brain power on a demanding day. But there are no life hacks for chronic sleep deprivation.
I hate to break it to you, but if you’re not sleeping enough at night, you just need to man up and start going to bed earlier — period.
Stay tuned and stay well,
Geo Espinosa, N.D., L.Ac, C.N.S., is a renowned naturopathic doctor recognized as an authority in integrative management of male and urological conditions. Dr. Geo is the founder and director of the Integrative Urology Center at New York University Langone Medical Center (NYULMC), a center of excellence in research and integrative treatments for urological conditions.
1. Faraut B, et al. J Clin Endocrinol Metab. 2015 Feb 10:jc20142566. [Epub ahead of print]
2. Leng Y, et al. Am J Epidemiol. 2014 May 1;179(9):1115-24.
3. Dhand R, et al. Curr Opin Pulm Med. 2006 Nov;12(6):379-82.
4. Lahl O, et al. J Sleep Res. 2008 Mar;17(1):3-10.
5. Leproult R, et al. Diabetes. 2014 Jun;63(6):1860-9.