Vitamins are organic compounds that the human body cannot produce and therefore must acquire through the diet. To help maintain good health, humans need 13 different vitamins. These include: vitamin A, the various B and D vitamins, vitamin C, vitamin E, and vitamin K. Deficiencies of these essential vitamins can cause the body to enter a diseased state. Deficiencies of different vitamins manifest themselves with differing diseased states. For example, night-blindness is linked to vitamin A deficiency, while Rickets is linked to vitamin D deficiency.

The relationship between foods and maintaining health has been recognized for centuries. For example, in 1747, Dr. James Lind discovered that citrus fruits prevented scurvy. Some stores of vitamins within the body can last well over a year, as is the case with vitamin B12. Others can deplete more rapidly