Vitamins 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. Unneeded water soluble vitamins are excreted from the body. The fat-soluble vitamins are A, D, E, and K. Vitamins are required to perform many functions in the body such as making red blood cells, synthesizing bone tissue, and playing a role in normal vision, nervous system function, and immune system function. Fat soluble vitamins are stored in the body in fat (and can become toxic when too much is consumed, almost always from supplements).
Vitamins and Their Major Functions3
Water Soluble
Vitamin Major Function
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
Vitamin Major Function
A Vision, reproduction, immune system function
D Bone and teeth health maintenance, immune system function
E Antioxidant, cell membrane protection
Vitamin Major Function
K Bone and teeth health maintenance, blood clotting
Vitamin deficiencies can cause severe health problems and even death. Some vitamins have been found to prevent certain disorders and diseases such as scurvy (vitamin C), night blindness (vitamin A), and rickets (vitamin D).