Do you sleep on your back, your side, or your stomach? Whichever one it is, there are specific consequences you might not know about. Here are four side effects that have to do with the way you sleep:

1. Sleeping on your stomach can cause back pain, because your spine isn’t supported. It makes you sleep with your head turned to one side, which is hard on your neck.

2. If you sleep on your back, you’re more likely to snore. But as long as you don’t prop your head up with too many pillows, it’s better for your spine than sleeping on your side or your stomach.

3. Sleeping on your left side puts more strain on your internal organs, including your liver, lungs, and stomach. Doctors usually tell pregnant women to sleep on their left side though, because it increases circulation to the baby.

4. Sleeping on your right side can cause heartburn. It’s not clear why, but several studies have found you’re more likely to wake up with heartburn if you fall asleep on your right side, opposed to your left.

Regardless of how you sleep, using an extra pillow for support can help. If you sleep on your back, put it under the arch of your spine. If you’re a side sleeper, put it between your knees, and if you’re on your stomach, put it right under your hips.