Numbness in the hands and feet is primarily caused by damage or dysfunction in the peripheral nerves, which transmit sensory and motor information between the brain/spinal cord and the rest of the body. This condition is often referred to as peripheral neuropathy and can result from various factors:

• Diabetes: One of the most common causes, where high blood sugar damages nerves, leading to numbness, tingling, or pain in the hands and feet

• Nerve Compression: Conditions like carpal tunnel syndrome (wrist nerve compression) and tarsal tunnel syndrome (ankle nerve compression) cause numbness due to pressure on specific nerves

• Spinal Issues: Herniated discs, spinal stenosis, or bone spurs can compress nerves exiting the spinal cord, causing numbness in limbs

• Vitamin Deficiencies: Lack of B vitamins (B1, B6, B12, folic acid) essential for nerve health can cause numbness

• Poor Blood Flow: Circulation problems reduce blood supply to nerves, causing numbness or tingling sensations

• Autoimmune Diseases: Disorders like multiple sclerosis, where the immune system attacks nerves, can cause numbness

• Other Causes: Infections (e.g., shingles, HIV), toxins (heavy metals, chemotherapy), metabolic problems (kidney failure, thyroid issues), trauma, and certain medications can also cause numbness

Symptoms often include gradual onset of numbness, tingling, burning pain, and sensitivity to touch, typically starting in a "stocking-glove" distribution affecting distal parts of limbs

. In summary, numbness in hands and feet is caused by nerve damage or dysfunction due to diabetes, nerve compression, spinal problems, vitamin deficiencies, poor circulation, autoimmune conditions, infections, toxins, or trauma

. Identifying the underlying cause is crucial for effective treatment.