Sleep is one of life’s necessities, yet getting comfortable can be difficult. You may settle into bed only to wake with a stiff neck, hear someone snoring, or find that heartburn keeps interrupting the night. Position can make a difference—but there is no single best side for everyone.
Adults ages 18 to 60 are generally advised to get at least seven hours of sleep a night. How you lie in bed may help with a particular concern, but it cannot replace enough sleep or treatment for an underlying sleep disorder.
Where Left-Side Sleeping May Help
Nighttime Heartburn
If acid reflux wakes you up, trying your left side is reasonable. Studies of people with gastroesophageal reflux disease have found less nighttime acid exposure when they sleep on the left rather than the right. That does not mean left-side sleeping guarantees a heartburn-free night, but it may be a useful change to try.
If symptoms are frequent or severe, speak with a healthcare professional instead of relying on position alone. You deserve a plan that addresses the problem, not just another uncomfortable night spent trying to stay on one side.
Sleep During Pregnancy
Position matters in late pregnancy, but the claim that only the left side is safe is misleading. After 28 weeks, guidance recommends going to sleep on your side rather than your back. Either the left or right side is acceptable. If you wake on your back, there is no need to panic; simply turn onto your side before returning to sleep.
A pillow behind your back or between your knees may make side sleeping more comfortable. Ask your maternity care team for advice if pain or another medical issue makes it hard to find a position that works.
Snoring
For some people, lying on the back allows the airway to narrow more during sleep. Turning onto either side—not necessarily the left—may reduce snoring. If your partner notices pauses in your breathing, or you wake gasping and feel unusually sleepy during the day, ask about an evaluation for sleep apnea. Position changes alone may not be enough.nhlbi.
Sleep apnea has effective treatments. A clinician may recommend side sleeping as one part of a plan, but may also discuss a breathing device or another treatment based on your symptoms and test results.
Find a Position You Can Maintain
There is little benefit in forcing yourself onto your left side if it causes shoulder or hip discomfort and keeps waking you. The best position is one that helps you sleep comfortably while taking any health needs into account. A supportive pillow or a small adjustment to your routine may be more helpful than trying to remain perfectly still all night.
Start with the reason you are considering a change. For reflux, the left side may be worth testing. For snoring, either side may help. In late pregnancy, aim to fall asleep on either side. And if poor sleep continues despite adjustments, seek advice rather than assuming your sleeping position is the only cause.
