Vitamin B is a complex of eight water soluble vitamins , active in cell metabolism . The name arises because it was once considered a single vitamin, much like Vitamin C or Vitamin D . Since later research has shown it is in fact a complex of chemically distinct vitamins that happen to often coexist in the same foods, the name has gradually declined in use, being replaced by the generic term "the B vitamins" , the vitamin B complex , or by the specific names of each vitamin.

Vitamin C is a nutrient required in very small amounts to allow a range of essential metabolic reactions in the body. Vitamin C is principally known as a water - soluble anti-oxidant and has been found to prevent scurvy . It is also known by the chemical name of its principal form, L-ascorbic acid or simply ascorbic acid . The guidance provided by the United States of America and Canada for Dietary Reference Intake (DRI) recommends 90mg per day and no more than 2g per day (2000mg/day). The article on ascorbic acid contains information on its chemical properties. This article describes its biological functions, discovery and the continuing scientific debate on how it is used by society, including its widespread application in doses larger than the officially recommended upper limit.