Subtitles section Play video Print subtitles SciShow is supported by Skillshare. Right now Skillshare is offering SciShow viewers two months of unlimited access to over 20,000 classes for free. Every night, when you turn out your light and pull up the covers, there's a good chance you settle into the same sleeping position. If you're like most people, you sleep on your side, with your knees tucked up in the fetal position. But lots of people also sleep on their back, sprawled out on their stomach, or twisted up around three pillows and a stuffed animal. But is one of those positions better than the others? There's a lot of pseudoscience out there, but the real answer is... well, it depends. If you're dozing off without a problem and not waking up with weird aches and pains, your setup is probably okay. But if you have some complaints, the way you sleep could be the issue. For example, sleeping on your right side seems to aggravate heartburn. None of the sample sizes were huge, but a handful of studies have shown that people lying on their right side after eating high-fat meals had higher levels of acid in their esophagus. We don't really know why that is, but some scientists think sleeping on that side relaxes the valve connecting your stomach and esophagus — the valve that normally keeps stomach acid where it belongs. So if you struggle with heartburn, it might be worth rolling over. As a bonus, sleeping on your left side may also improve circulation, although focused studies haven't really looked at it. Your body returns blood to your heart from the right side, so sleeping on the left means those vessels aren't being compressed by your body weight. Left-side sleeping is also recommended for people who are pregnant. Better blood-flow means more blood and nutrients to the placenta. It also keeps the growing uterus from compressing the liver, which is on the right. Sleeping on your side might also be good for your brain — at least, if we're anything like mice. Using MRI scans, a 2015 study in the Journal of Neuroscience found that eight rats sleeping on their right side cleared waste from their brains more efficiently than seven rats on their stomach or nine on their back. Side-sleeping is the most common in mice, just like it is with humans, and the authors speculated that animals may have evolved to sleep like this because it's the best way to clear brain waste. But until we replicate this study in people, it's probably not worth shaking up your routine. Now, side sleeping has its pros and cons, but if there's any position that's the worst, it's probably sleeping on your stomach. This puts pressure on your entire body and doesn't let the spine sit naturally. And if you turn your face sideways to breathe, that also awkwardly contorts your neck. So, if you wake up feeling sore, and you sleep on your stomach, it might be something to think about. If this is really your jam, though, a flatter pillow can at least help reduce neck strain. On the flip side — literally — sleeping on your back puts your spine in a neutral position, so it can be good for back pain. It also keeps your head elevated on a pillow, where gravity can keep stomach acid out of your esophagus and cut down on heartburn. But sleeping on your back with your head on a pillow also makes your neck flex forward, which tightens your airway and makes it harder for air to pass through. That can make snoring and sleep apnea — a condition that causes breathing to stop and start during sleep — more severe. Ultimately, though, the best sleeping position seems to depend on the person. If you're pregnant or snore, some might be more beneficial than others. But in general, if you're comfortable, whatever sends you off to dreamland best is probably perfectly fine. And one great way I've found to get a solid night's sleep is to be tired from learning and trying new things. Skillshare is perfect for that. With over 20,000 classes, you'll never run out of things to learn, but the classes still feel small and personal. Through Skillshare you have access to teachers who are experts in their field, like best-selling author and award-winning educator Peggy Dean, who teaches calligraphy, botanical line drawing, and how to price your work as a freelancer. Just to name a few. Skillshare is always adding new features, like Skillshare Talks where teachers pull back the curtain on how they approach their work. One reason we at SciShow connected with Peggy Dean was because of her Skillshare Talk about how when you're interested in something, whether it's fire dancing, or the best position to sleep in, you just want to research and learn more and more. So to get 2 months of Skillshare membership for free and to check out Peggy Dean and all the other great teachers, click on the link in the description. And let us know what classes you take!