Sleeping on your right side is perfectly fine for most people. It offers many of the same benefits as left-side sleeping, including reduced snoring and better breathing compared to sleeping on your back. The differences between right and left side sleeping are small and only matter for a few specific conditions, most notably acid reflux and heart failure.
How Right-Side Sleeping Affects Your Heart
For people with healthy hearts, sleeping on either side is unlikely to make a meaningful difference. But for people with heart failure, right-side sleeping can actually be the more comfortable choice. People with heart failure often experience shortness of breath that gets worse when they lie on their left side, because the weight of the heart shifts and puts extra pressure on the already-struggling pump. Many naturally migrate to their right side for relief.
One study found that right-side sleeping may also be the best position for reducing obstructive sleep apnea, possibly because of how it affects blood flow to and from the heart. More broadly, sleeping on either side is significantly better than sleeping on your back for sleep apnea. Over half of people with obstructive sleep apnea have worse symptoms when they sleep face-up.
The Acid Reflux Exception
This is where right-side sleeping has a genuine downside. If you deal with heartburn or gastroesophageal reflux, sleeping on your left side is measurably better. A study of 57 people with chronic heartburn found that while the number of reflux episodes was roughly the same regardless of position, acid cleared from the esophagus much faster when participants slept on their left side compared to their right side or back.
The reason is anatomical. Your stomach curves to the left. When you lie on your right side, the junction between your stomach and esophagus sits below the level of stomach acid, making it easier for acid to creep upward. Right-side sleeping also relaxes the muscular valve connecting the stomach to the esophagus. If you don’t have reflux issues, none of this matters. If you do, switching to your left side at night is one of the simplest things you can try.
Right-Side Sleeping During Pregnancy
Pregnant women have long been told to sleep on their left side, and some worry that right-side sleeping could be harmful. A large meta-analysis published in The Lancet put this concern to rest. Researchers pooled individual data from multiple studies and found that going to sleep on the right side carried essentially the same risk of late stillbirth as sleeping on the left. The adjusted odds ratio was 1.04, meaning no meaningful difference.
The real position to avoid in late pregnancy is flat on your back. Supine sleeping can compress the large vein that returns blood to your heart, reducing blood flow to the uterus. Either side is a safe alternative. Left-side sleeping does put slightly less pressure on the liver and may increase blood flow to the kidneys and fetus, which is why it gets recommended more often. But if you wake up on your right side, there’s no reason to worry.
Brain Waste Clearance During Sleep
Your brain has a waste-removal system that works most actively during sleep, flushing out proteins linked to neurodegenerative disease. Research using imaging and radioactive tracers found that this system works most efficiently when sleeping in a lateral (side) position compared to sleeping on your back or stomach. The study did not find a significant difference between right and left lateral positions. Sleeping on your stomach, which puts the head in the most upright position, showed the slowest waste clearance.
Who Should Avoid Right-Side Sleeping
For most people, sleeping on your right side is a good position. Side sleeping in general protects against snoring, sleep apnea, and back pain better than sleeping face-up or face-down. The only groups that benefit from specifically choosing the left side over the right are people with frequent heartburn or GERD, where left-side sleeping helps acid drain away from the esophagus faster.
People with heart failure may actually find the opposite: right-side sleeping feels easier on breathing. And pregnant women can rest assured that both sides are equally safe for the baby, though back sleeping should be avoided in the third trimester.
If you naturally gravitate to your right side and don’t have acid reflux, there’s no reason to force yourself into a different position. Sleep quality depends far more on comfort, consistency, and getting enough hours than on which side you choose.