Vitamin B6 is a water-soluble vitamin. Water-soluble vitamins dissolve in water so the body cannot store them. Leftover amounts of the vitamin leave the body through the urine. Although the body maintains a small pool of water-soluble vitamins, they have to be taken regularly. Lack of vitamin B6 in the body is uncommon. It can occur in people with kidney failure, liver disease, or alcohol dependence. Function Vitamin B6 helps the body to:
Make antibodies. Antibodies are needed to fight many viruses, infections, and other diseases. Maintain normal nerve function. Make hemoglobin. Hemoglobin carries oxygen in the red blood cells to the tissues. A vitamin B6 deficiency can cause a form of anemia. Break down proteins. The more protein you eat, the more vitamin B6 you need. Keep blood sugar (glucose) in normal ranges.  Side Effects Large doses of vitamin B6 can cause:
Difficulty coordinating movement Numbness Sensory changes  Deficiency of this vitamin can cause:
Confusion Depression Irritability Mouth and tongue sores also known as glossitis Peripheral neuropathy  (Vitamin B6 deficiency is not common in the United States.)