1. Bolstered Lymphatic System
Ayurvedic medicine has long said that sleeping on your left side helps the body filter waste through the lymph nodes. That’s because most of our lymph drains to the left in any case through the thoracic duct. Sleeping on that side gives a gravity boost to the process.
Western medicine supports this idea, with evidence that left-sided sleep improves the breakdown of waste materials from the brain as well. During slumber, your brains uses cerebrospinal fluid to clear out toxins and other waste, using a system of lymphatic vessels to move them out. Sleeping on the right is thought to impede the open flow of lymph.