Vitamin B6 is a water-soluble vitamin and is part of the vitamin B complex. Vitamin B6 plays a role in the synthesis of antibodies by the immune system, which are needed to fight many diseases. It helps maintain normal nerve function and also acts in the formation of red blood cells. Vitamin B6 is also required for the chemical reactions needed to digest proteins. The higher the protein intake, the more the need for vitamin B6.

Large doses of vitamin B6 can cause neurological disorders and numbness. Deficiency of this vitamin can cause mouth and tongue sores, irritability, confusion, and depression. Vitamin B6 deficiency is uncommon in the United States.