Pure Encapsulations B-Complex Plus, B vitamins are essential for the proper functioning of the nervous system and are perhaps the most important nutritional factor for healthy nerve cells. The B vitamins also play a role in the conversion of carbohydrates into energy, in the metabolism of fats and protein, and in the maintenance of muscle tone in the GI tract. The B vitamins support the integrity of the skin, hair, and liver. This balanced combination of functionally interrelated B vitamins provides wide ranging benefits, yet is specifically supportive of the nervous system.