Molecular Nutrition

In this book Molecular Nutrition: Vitamins we focus on Vitamins. In total
there are 13 vitamins which are essential constituents of the diet. Vitamins
are classified as either fat soluble (A, D, E, and K) or water soluble
(B1, B2, B3, B5, B6, B7 B9, B12, and C) and are termed as micronutrients
due to the low quantities required in the diet. The majority of vitamins,
except for vitamin D and small amounts of B3, need to be obtained from
the diet, and thus inadequate intake can lead to deficiencies. The most
common deficiencies in the United States are of vitamin B6, vitamin B12,

vitamin C, folic acid, and vitamin D, with the deficiency subject to varia-
tion depending on the ethnic group, gender, and age of the person.

Furthermore, the quantity of vitamin required from the diet varies quite
significantly between vitamins from micrograms to milligrams.