If you’re anything like me, you’ve probably never given much thought to the position you adopt while sleeping. After a long day—work, kids, cooking, some relaxation—you’re more likely to fall into bed and crash rather than consciously think about the side you’re lying on.

For most of us, sleep is about getting enough rest to function the next day. But what if the way you sleep could influence your health? Turns out, it can.

While we all have our favorite sleeping styles—whether on our back, right side, or left side—there’s growing evidence that sleeping on your left side offers a surprising range of health benefits. Here’s a closer look at why you might want to reconsider how you catch your z’s.

1. Relief from Heartburn

If you’re prone to acid reflux or nighttime heartburn, sleeping on your left side could bring relief. This position helps keep your stomach below your esophagus, reducing the chances of stomach acid creeping up and causing that unpleasant burning sensation. Left-side sleeping aligns your internal organs in a way that makes it easier for gravity to keep acid where it belongs.

2. Boosted Spleen and Liver Function

Your spleen, located on the left side of your body, plays a vital role in filtering impurities and supporting your immune system. Sleeping on your left side improves blood flow to the spleen, helping it function more effectively.

Similarly, your liver benefits from this position. Since it’s on the right side of your body, sleeping on your left encourages optimal detoxification and toxin processing by keeping pressure off the liver and aiding its natural functions.

3. Better for Pregnant Women

Pregnant women, especially in the third trimester, are often advised to sleep on their left side. Why? This position supports better blood circulation, which is crucial for both mother and baby. It also reduces pressure on the liver, improving overall comfort and heart function. Meanwhile, sleeping on the back during pregnancy has been linked to risks like stillbirth in some cases, making side-sleeping a safer option.

4. Promotes Healthy Bowel Movement

Your digestive health might also benefit from left-side sleeping. The ileocecal valve, which connects your small intestine to your large intestine, is located on your left. This position helps gravity do its job, aiding waste movement through the intestines and promoting healthy bowel movements. If regularity is an issue, your sleeping position could make a difference.