Numbness of the feet is not an indicator of how long a person can live, its related to the etiology of the onset of the disease, such as physiological causes, lumbar disc herniation, etc. The life expectancy is the same as a normal person. If Greenbrier syndrome is severe, it can be life-threatening in hours or days. 1. Physiological causes: the lower limbs are compressed due to incorrect posture, etc. When the compression is lifted, the limbs will return to normal, which is a physiological factor and can be relieved after the compression is lifted. 2. Herniated lumbar intervertebral disc: When the herniated lumbar intervertebral disc compresses the nerve root, the symptom of numbness of both feet can appear. This disease can be clinically cured or effectively relieved through active treatment, and will not affect the patient’s life expectancy. 3. Guillain-Barre Syndrome: It is a disease of demyelination of spinal nerves and peripheral nerves, with clinical manifestations of progressive ascending symmetrical paralysis, and respiratory depression if the respiratory muscles are involved, resulting in respiratory distress and death. Numbness of the feet can also be caused by other diseases, it is recommended that patients pay attention to clarify the cause, and actively seek medical treatment, so as not to cause adverse consequences.