Regulate body processes and promote normal body-system functions.

The thirteen vitamins are categorized as either water-soluble or fat-soluble.

The water-soluble vitamins are vitamin C and all the B vitamins, which include thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folate and cobalamin. 

The fat-soluble vitamins are A, D, E, and K. Vitamins are required to perform many functions in the body such as assisting in energy production, making red blood cells, synthesizing bone tissue, and supporting normal vision, nervous system function, and immune system function. 

Vitamin deficiencies can cause severe health problems and even death.  For example, a deficiency in niacin causes a disease called pellagra, which was common in the early twentieth century in some parts of America. The common signs and symptoms of pellagra are known as the “4D’s—diarrhea, dermatitis, dementia, and death.”   Until scientists discovered that better diets relieved the signs and symptoms of pellagra, many people with the disease ended up hospitalized in insane asylums awaiting death.  Other vitamins were also found to prevent certain disorders and diseases such as scurvy (vitamin C), night blindness (vitamin A), and rickets (vitamin D).

Water Soluble Vitamins
Thiamin (B1)

Coenzyme, energy metabolism assistance

Riboflavin (B2 )

Coenzyme, energy metabolism assistance

Niacin (B3)

Coenzyme, energy metabolism assistance

Pantothenic acid (B5)

Coenzyme, energy metabolism assistance

Pyridoxine (B6)

Coenzyme, amino acid synthesis assistance

Biotin (B7)

Coenzyme, amino acid and fatty acid metabolism

Folate (B9)

Coenzyme, essential for growth

Cobalamin (B12)

Coenzyme, red blood cell synthesis

C (ascorbic acid)

Collagen synthesis, antioxidant

Fat-Soluble Vitamins

Vision, reproduction, immune system function


Bone and teeth health maintenance, immune system function


Antioxidant, cell membrane protection


Bone and teeth health maintenance, blood clotting