This Is What Sleeping On The Left Side Does For Our Brain, Stomach & Glymphatic Health

Many individuals default to side sleeping as their preferred position, yet they may not realize its associated health advantages. Indeed, various sleeping positions can yield diverse effects on the body, both beneficial and detrimental. Generally, it's advisable for individuals to sleep in whatever position feels most comfortable to them. However, if they experience symptoms such as back pain, jaw discomfort, indigestion, and others, they might contemplate altering their sleeping posture. To delve into specifics, opting to sleep on the left side could be worth considering.

The Benefits of Sleeping on You Left Side

Minimize back discomfort – Sleeping on the stomach may strain the spine and result in pain. Side sleeping maintains the spine in a naturally aligned position, alleviating pressure on the lower back.

Decrease snoring – Sleeping on the back can cause the tongue and soft palate to slide backward, partially obstructing the airway and leading to increased snoring, a common issue for those with sleep apnea. Side sleeping helps keep the tongue forward and the airway unobstructed.

Enhance digestion – Sleeping on the left side, specifically, may alleviate certain gastrointestinal issues such as bloating, constipation, and heartburn. Since the stomach resides on the left side of the body, lying in that position enables gravity to assist in the digestion process.

Potential brain health benefits – It's not widely known that the brain eliminates waste while you sleep. Research suggests that side sleeping may enhance this process by supporting the glymphatic system, which functions similarly to our lymphatic system but within the central nervous system. Animal studies indicate that this could potentially reduce the risk of conditions like Alzheimer’s and Parkinson’s disease. However, further research on humans is required to better understand and validate these findings.

Enhances blood flow – Optimal circulation is essential during pregnancy to facilitate blood flow to the placenta. This is why it's advised for expectant mothers to sleep in this position.

How to Train Yourself to Sleep on Your Side

Choose a good pillow and mattress 

  • Find a pillow well-suited to your collarbone structure.
  • Ensure the pillow is firm enough to support the neck.
  • Mattresses must often be softer to prevent pressure from building in the shoulders and hips.

Use pillows as barriers and supports

  • Put a pillow between your knees to support your hips and lower back
  • You can also hug a pillow to comfortably rest your upper arm. 
  • Invest in body pillows to maintain your position.
  • Sew a tennis ball onto the back of a shirt to prevent yourself from rolling over.

Sleep on the couch at first

  • Couches are often narrow and only have room for side sleeping anyway.

Disadvantages of Sleeping on Your Side

Although this position could provide many benefits, it’s not for everyone, especially those who use mattresses and pillows that make side sleeping uncomfortable. These disadvantages include:

  • Pain in the shoulders and hips

Side sleeping on too-firm mattresses could increase pressure on the shoulders, hips, and knees. However, too-soft mattresses could cause the spine to go out of alignment and also cause pain.

  • Pressure in the face

People with sinus congestion and glaucoma may experience painful or uncomfortable pressure in their faces when they lie on their sides. Additionally, it could worsen a tight or stiff jaw.

The Benefits and Disadvantages of other Sleeping Positions

In the end, individuals should prioritize sleeping in the manner that feels most comfortable to them. However, it's essential to acknowledge how your sleep position may impact your body, whether positively or negatively. Beginning your nights on your left side and allowing your body to naturally settle into its preferred position can be beneficial. Additionally, sleeping on the right side also offers advantages, so there's no need to fret about trying to retrain yourself if it doesn't come naturally. Similarly, there are both benefits and drawbacks to sleeping on the back and stomach.

Sleeping on your back

Benefits – It may help with:

  • Hip pain
  • Knee pain
  • Arthritis
  • Fibromyalgia
  • Sinus congestion
  • Bursitis 


  • Place a pillow under your knees to support the spine and lower back.
  • Spread the legs and arms out to reduce pressure on the joints.
  • Choose a pillow that offers good support for the neck, and avoid the ones that tilt your chin toward your chest.
  • Elevate the head with extra pillows or a wedge pillow to help reduce heartburn, headaches, and sinus buildups. 

Sleeping on your stomach

Regrettably for enthusiasts of this position, experts caution against it. "If you find yourself experiencing back pain while sleeping on your stomach, there's likely a cause," says Bill Fish, a certified sleep science coach. "Given that the bulk of the body's weight is concentrated around the center, this core pressure sinks deeper into the sleep surface, exerting strain on the spine in an unfavorable direction, leading to back and neck discomfort."

Still, here are some tips for those who can’t switch to their side:

  • Use a flat pillow or none at all.
  • Don’t tuck your arms under your pillow or head, since this could cause arm numbness or shoulder joint pain. 
  • Alternate the sides of your head to avoid neck pain.
  • Don’t lift your leg to one side with a bent knee since this could worsen back issues.


1. “Side Sleeping: Which Side Is Best and How to Train Yourself to Do It.” CNET. Taylor Leamey. July 7, 2022

2. “Could body posture during sleep affect how your brain clears waste?” Science Daily. August 4, 2015

3. “How These 3 Sleep Positions Affect Your Gut Health.” Healthline. Jennifer Chesak. March 20, 2023

0/Post a Comment/Comments

Previous Post Next Post