Improved gastric emptying
Better alignment with the descending colon
Support for natural digestive movement
Although more research is needed, the theory aligns well with digestive anatomy.
3. May Support Lymphatic Drainage
Evidence level: Emerging
The lymphatic system plays an important role in removing waste and supporting immune health.
A major lymphatic vessel called the thoracic duct drains toward the left side of the body. Some researchers believe sleeping on the left side may help support natural lymphatic flow.
While human studies are still limited, the anatomical reasoning is promising.
4. May Support Brain Waste Clearance
Evidence level: Early research
During sleep, the brain uses the Glymphatic system to clear metabolic waste products.
Animal studies suggest side-sleeping positions may help this process work more efficiently compared to lying flat on the back.
