How Sleeping on Your Left Side Can Boost Your Health, According to Science

We all know that getting quality sleep is essential for good health. But did you know that your sleeping position can significantly impact your physical well-being? Research shows that the way you sleep affects your spine, digestion, circulation, and even your brain health. Among the most beneficial positions? Sleeping on your left side.

In this article, we’ll explore the best and worst sleeping positions, and dive into the science-backed benefits of left-side sleeping—from easing heartburn to supporting your brain and organs.

🚫 The Worst Sleeping Position: On Your Stomach

Sleeping on your stomach is considered the least healthy position. While it may reduce snoring, it comes at a cost:

• Puts strain on your neck, spine, and shoulders

• Increases pressure on joints and muscles

• Can cause numbness, tingling, and poor alignment

💡 Pro tip: If you can’t sleep any other way, place a pillow under your pelvis and lower abdomen to reduce strain. Avoid using a pillow under your head unless it feels comfortable.

✅ Why Sleeping on Your Left Side Is the Best Position

Did you know? Over 60% of Americans sleep on their side, and research shows it’s the healthiest sleep posture—especially the left side.

💓 1. Supports Heart Health and Circulation (Especially During Pregnancy)

Sleeping on your left side improves blood flow, making it the best choice for pregnant women. It helps:

• Enhance circulation from the heart to the placenta

• Prevent pressure on the liver

• Reduce swelling and improve oxygen flow to the baby

👉 Doctors recommend left-side sleeping during the second and third trimesters of pregnancy for optimal maternal and fetal health.

🔥 2. Reduces Acid Reflux and Heartburn

Struggle with acid reflux or GERD at night? Research shows that sleeping on your left side can significantly reduce symptoms.

📊 A study published in the Journal of Clinical Gastroenterology found that left-side sleepers experienced fewer episodes of acid reflux than those who slept on their right side.

Why? Experts believe this position helps keep stomach acid below the esophagus, preventing upward flow that causes heartburn.

🧠 3. May Help Protect Brain Health and Reduce Alzheimer’s Risk

A groundbreaking study from Stony Brook University suggests that sleeping on your side helps clear brain waste more effectively than sleeping on your back or stomach.

This process—called the glymphatic system—removes toxins and protein buildup, which, if left unchecked, may increase the risk of neurodegenerative diseases like Alzheimer’s.

🧬 Deep side sleeping = better brain detox = lower long-term risk.

😴 4. Helps Prevent Snoring and Sleep Apnea

If you or your partner snores, sleeping on the back may be the culprit.

• Back sleeping can cause the tongue to collapse, blocking airways

• Left-side sleeping helps keep airways open, reducing snoring and sleep apnea symptoms

🏥 According to the Mayo Clinic, side sleeping is often the first line of treatment for obstructive sleep apnea.

🧬 5. Improves Lymphatic and Digestive Function

The lymphatic system plays a key role in clearing waste from the body. Left-side sleeping helps this process by:

• Supporting lymph drainage into the thoracic duct (located on the left)

• Enhancing digestion, as the stomach and pancreas hang naturally on the left, promoting smoother food breakdown

⚖️ 6. Good for Kidney Health — But Switch Sides Occasionally

A 2001 study published in BMJ suggested that people who sleep on the same side every night may be at higher risk of developing kidney stones on that side.

💡 Tip: Alternate sleeping sides to support kidney circulation and reduce risk of stone formation. Variety in sleep posture can help protect your organs.

😕 What About Sleeping on Your Back?

While better than stomach sleeping, back sleeping has its drawbacks:

Pros:

• Keeps head, neck, and spine aligned

• May reduce facial wrinkles and pressure points

Cons:

• Can worsen snoring and sleep apnea

• Not recommended for pregnant women in later stages due to restricted blood flow from uterus pressure

💡 Solution: Place a pillow under your knees and a small rolled towel under your lower back for support.

🌿 7 Easy Tips to Improve Your Sleep Quality (No Matter the Position)

Regardless of how you sleep, these science-backed habits can help you fall asleep faster and stay asleep longer:

1. Eat sleep-promoting foods like bananas, almonds, or oats

2. Use essential oils like lavender or chamomile for relaxation

3. Practice deep breathing or meditation before bed

4. Use herbs like valerian root or passionflower

5. Keep your bedroom dark, cool, and quiet

6. Try a simple 2-ingredient sleep drink (e.g., warm milk with honey)

7. Add air-purifying plants like snake plant or aloe vera to your room

💤 Final Thoughts: Should You Start Sleeping on Your Left Side?

The evidence is clear: sleeping on your left side offers numerous health benefits, from reducing acid reflux to improving brain and heart health. While no position is perfect for everyone, left-side sleeping is considered the best overall posture for long-term wellness.

If you’re not already doing it, try sleeping on your left side for a week and see how you feel. You might notice improvements in digestion, sleep quality, and overall comfort.