Why Sleeping on Your Left Side May Be Better for Your Health

Side sleeping is one of the most common sleep positions, yet many people don’t realize how much sleep posture can influence overall health. From back pain and digestion to snoring and circulation, the way you sleep affects far more than comfort alone.

If you struggle with lower-back pain, jaw tension, heartburn, or restless sleep, adjusting your sleep position—especially shifting to your left side—may help relieve certain symptoms without medication or major lifestyle changes.

Benefits of Sleeping on Your Left Side

1. Reduced Back and Spine Strain

Sleeping on your stomach places excessive pressure on the spine and forces the neck into unnatural angles. Side sleeping, especially with proper pillow support, helps maintain neutral spinal alignment.

When your spine stays aligned, pressure on the lower back decreases, which may reduce stiffness, soreness, and chronic discomfort over time.

2. Less Snoring and Improved Breathing

Back sleeping allows gravity to pull the tongue and soft tissues backward, partially blocking the airway. This often leads to snoring or worsened sleep apnea.

Side sleeping helps keep the airway open, improving airflow and reducing throat vibrations. For people who snore or experience mild sleep-disordered breathing, this change alone can make a noticeable difference.

3. Improved Digestion and Reduced Heartburn

Sleeping on the left side may support better digestion and ease symptoms like bloating, constipation, and acid reflux.

Because the stomach sits on the left side of the body, gravity helps keep stomach acid lower and encourages smoother movement of food through the intestines. This position is often recommended for people who experience nighttime heartburn or GERD.

4. Potential Brain Health Support

During sleep, the brain clears metabolic waste through the glymphatic system, a process similar to lymphatic drainage.

Some research—primarily animal studies—suggests side sleeping may enhance this waste-clearing process, potentially supporting long-term brain health. While human research is still limited, early findings are promising.

Note: More large-scale human studies are needed to confirm these effects.

5. Better Blood Circulation (Especially During Pregnancy)

Left-side sleeping is often recommended during pregnancy because it helps improve circulation to the placenta and vital organs. This position reduces pressure on major blood vessels and supports optimal oxygen and nutrient flow.

Even outside of pregnancy, improved circulation can support heart health and reduce nighttime discomfort.

How to Train Yourself to Sleep on Your Side

Choose the Right Pillow and Mattress

• Use a pillow that supports your neck while keeping your head aligned with your spine
• Avoid pillows that push your chin toward your chest
• Choose a mattress that cushions the shoulders and hips without allowing the spine to sink

Use Pillows for Extra Support

• Place a pillow between your knees to reduce hip and lower-back strain
• Hug a pillow to support the upper arm and prevent shoulder collapse
• Consider a full-length body pillow to help maintain position all night

Prevent Rolling Onto Your Back

• Sew a tennis ball into the back of a sleep shirt to discourage rolling
• Try sleeping on a couch at first—the narrow surface naturally encourages side sleeping

Potential Downsides of Side Sleeping

Side sleeping isn’t perfect for everyone. Possible drawbacks include:

Shoulder and Hip Pain

• Mattresses that are too firm can create pressure points
• Mattresses that are too soft may misalign the spine
  Finding the right balance is essential.

Facial Pressure and Jaw Discomfort

People with sinus congestion, glaucoma, or jaw tension may notice increased facial pressure—especially without proper pillow support. Adjusting pillow height and firmness can help reduce this issue.

How Other Sleeping Positions Compare

Sleeping on Your Back

May help with:

• Hip and knee pain
• Arthritis or fibromyalgia
• Sinus congestion

Helpful tips:

• Place a pillow under your knees
• Use a supportive neck pillow
• Slightly elevate the head to reduce heartburn
• Spread arms and legs to reduce joint strain

Sleeping on Your Stomach (Least Recommended)

Sleep experts generally advise against stomach sleeping because it places significant stress on the spine and neck.

“Since most of the body’s weight is centered in the core, stomach sleeping pushes the spine in the wrong direction, causing back and neck pain,” explains sleep science coach Bill Fish.

If you can’t avoid it:

• Use a very flat pillow or none at all
• Avoid tucking arms under your head
• Alternate head direction to reduce neck stiffness
• Keep legs straight to prevent lower-back strain

The Bottom Line

There’s no single “perfect” sleep position for everyone. However, being mindful of how your sleep posture affects your body can lead to better rest, less pain, and improved overall health.

If you’re unsure where to start, sleeping on your left side is often a helpful and low-risk option. Over time, your body may naturally adapt.

Ultimately, the best position is the one that helps you wake up feeling rested, comfortable, and refreshed.