are a very diverse group of nutrients divided into two types:
- Fat soluble: Vitamins A, D, E and K. These vitamins are essential to a healthy life, are required in small quantities (micrograms or less) per day, and the excess is stored in the liver and body fat.
- Water soluble: thiamin (B1), riboflavin (B2), niacin (B3), pyridoxine (B6), pantothenic acid, folic acid, biotin, cobalamin (B12), choline, and carnitine. These vitamins are essential to a healthy life and are required in small quantities (micrograms or less) per day as well.
However, water soluble vitamins (except for B12
) are not stored in the body and therefore must be consumed daily. B12
is stored in the liver, and it has been estimated that most healthy people, dogs, and cats have a 2-5 year supply stored in the liver.