Sleeping on your back can easily cause numbness in the feet, the following common causes: First, sleeping on your back will lead to abdominal pressure, thoracic pressure, causing increased pressure in the thoracic and abdominal cavity, which affects blood circulation, resulting in reduced blood supply to the lower limbs. Reduced blood supply for a long time, will make the lower extremities numbness symptoms, especially numbness in the feet performance. Second, sleeping on your stomach for a long time can also increase the pressure in the spinal canal, mainly due to the transfer of pressure from the thoracoabdominal cavity to the spinal canal. Increased pressure in the spinal canal will make the patient’s original lumbar disc herniation, as well as lumbar spinal stenosis and other diseases aggravated, so that the nerve root pressure, resulting in the clinical symptoms of numbness in the feet. Therefore, it is best not to sleep on your back, and you should constantly change your position to avoid maintaining a single position to cause the corresponding clinical symptoms.