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Study after study has shown that napping is awesome, even for young healthy adults who get enough sleep at night.  On average, people feel better after catching a few Zs, and their brains work better, too, which might make you wonder, should everyone be napping?  Well, not necessarily.  The answer is more complicated than you might think.

Lots of people swear by naps.  In the US, for example, about half of adults nap in a given week, and there's been a ton of research on napping which suggests the benefits are impressive.  Post-nap, people do better on tests that measure math skills, logic, reaction time, memory, mood, all kinds of things really, and on some tests, a nap is even better than caffeine, but such results are a bit biased, because a lot of this work has been done in people who are either sleep-deprived or habitual nappers, and the studies the gains for people who nap regularly are so great that even if a study includes non-nappers, the nappers' benefits can skew the results of the whole group.

Now, it makes sense that researchers have relied so heavily on nappers and people who are downright exhausted.  It's not exactly easy to fall asleep in the middle of the day in a weird lab bedroom with wires attached to you, but it also means we're only now starting to figure out who benefits from napping and why, and while naps are great on average, not everyone benefits equally.  

When researchers have taken pains to look at a more representative sample, they've been able to tease out some differences between people who nap regularly and those who don't.  Non-nappers typically don't get a cognitive boost when napping.  Lots of times, they just wake up feeling groggy and it may be because there are differences in what happens in their brains when they nap.  Non-nappers spend more time in deeper sleep, which could make it harder for them to wake up.  They also have fewer brain wave signatures of memory consolidation when new information moves into long term storage, which could explain why they don't perform better on memory tests post-nap, but what if non-nappers just need more practice napping?

Researchers looked into that question for a study published in 2018.  They put non-habitual nappers on a training regimen to try to build up their napping skills.  Basically, participants took a 20 minute nap three times a week, and after four weeks, it made zero difference.  They still had the same patterns of brainwaves during a nap, they woke up feeling just as groggy, and they did no better on cognitive tests.  

That could be because nap aversion is hardwired.   There's some evidence that it may come down to the gene variations that you're born with and your childhood napping habits.  Non-nappers could just be people who have learned through experience that napping doesn't work for them, or it could be that the participants simply didn't train long or hard enough, but even if everyone could learn to nap like the pros, there are a few other caveats to consider before we say they should.

For shift workers and people with sleep disorders or atypical sleep schedules, things get even more complicated, and even though older adults are more likely to take naps than younger folks, napping in seniors is associated with higher rates of some pretty nasty health outcomes.  There's no direct evidence that napping is causing these problems, but we need more information about this connection before we can say napping is great for this group.

Still, if you are a younger healthy adult who enjoys a good siesta, you'll probably get a lot out of napping regularly, and there's plenty of science that can help you optimize your routine.  Research says the sweet spot for nap length is somewhere around 10-30 minutes.  Anything shorter is not restful, much longer than that, and you'll wake up groggy, and the best time of day to nap seems to be sometime in the 2-5 pm window.  This could be because circadian rhythms naturally dip in the afternoon, hence that mid-afternoon lull, and that may make it easier to fall asleep, which is definitely an important factor in napping success, but there's also evidence that late day naps interfere with nighttime sleep, so it may just be that 2-5 is early enough to avoid that.

So even if you usually avoid naps, you could try following these best practices and see if napping does anything for you, but if it doesn't work out, you don't need to feel bad.  Your brain might just work a little differently.  

Thanks to (?~3:41) for asking and thanks to all of our other Patrons who voted for this question in our poll.  You can find out more about joining our Patron community at patreon.com/scishow and one more quick tip: you might get the most benefits of all if you combine your nap with caffeine.  We have a whole episode that explains why and how to pull it off, so why not watch that one next?

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