Vitamins are defined as substances that our bodies require for optimal development and function. Vitamins A, C, D, E, and K, as well as choline and B vitamins (thiamin, riboflavin, niacin, pantothenic acid, biotin, vitamin B6, vitamin B12, and folate/folic acid), are all essential.
All of the B vitamins, as well as vitamin C, are water-soluble vitamins. Water-soluble vitamins are difficult to store in the body, so any excess is excreted in the urine.
Vitamins can’t be produced in large enough amounts to fulfill human needs, therefore they have to come from food or a synthetic source. Vitamins are referred to be important nutrients because of this.