AboutVitamin B6 is a water-soluble B-Complex vitamin. There are multiple forms of this vitamin naturally present in many foods and commonly added to others. The two most common forms used in supplements are pyridoxine HCl and pyridoxal-5-phosphate “PLP”. When consumed as pyridoxine HCl, it is converted to the metabolically active coenzyme “PLP” form in the body before use. The main function of PLP is connected to its role as a coenzyme to more than 60 enzymes that catalyze essential chemical reactions in the body. It plays a vital role in protein, carbohydrate, and lipid metabolism, neurotransmitter synthesis, red blood cell formation, niacin formation, and supporting immune defense.