B vitamins belong to a set of water-soluble vitamins, or say a class of water-soluble vitamins. B vitamins are important in cell metabolism. Cells are the most essential part of our human body, since our body is made of different kinds of cells, which makes B vitamins essential for humans. There are a number of B vitamins. These vitamins are members of the set B vitamins. Almost each of them holds similar names. However, they have proven to be different in their chemical characteristics and behavior. Scientific research has proven this true. It is possible that several B vitamins can be acquired through a single food item. There are eight vitamins in total, which fall under the category of B vitamin or are members of the set of B vitamins. It is possible that a single food item (scientifically known as dietary supplement) consists of all eight B vitamins. Such dietary supplement is known as vitamin B complex. Individual B vitamins are separated by giving them unique names according to their characteristics and chemical behavior.