The word vitamin was invented in 1911. It is made from a connection of two words; vita, which means life and amine, a word which refers to a nitrogen compound, i.e. vital nitrogen compounds (amines).
As more vitamins were discovered it became clear that not all vitamins contain nitrogen compounds, but the name has been kept.
Without vitamins we develop avitaminosis, potentially mortal deficiency illnesses.
Vitamins are divided into two categories.
Water soluble vitamines.
The water soluble vitamins are the vitamin Bs and vitamin C. Most of them also function as co-enzymes. Water soluble vitamins are only stored in small amounts in the body, so they must be supplemented to avoid deficency symptoms. Water soluble vitamins are measured in milligrammes = mg.
Fat soluble vitamins
Fat soluble vitamins include vitamin A, vitamin D, vitamin E, and vitamin K. These vitamins are stored in the body, so we can do without them for some time before deficiency diseases set in. The fat soluble vitamins were formerly measured in international units = I.U. Nowadays, however, they are also measured in microgrammes (mcg.).
Conversion
Vitamin A: 1 I.U. = 0.3 mcg. of retinol
Beta-carotene: 1 I.U: = 0.6 mcg. of beta-carotene
Vitamin D: 1 I.U. = 0.025 mcg. of cholecalcipherol
Vitamin E: 1 I.U. = 0.67 mg. of d-a-tocopherol
Antioxidants
Some vitamins are antioxidants, i.e. they neutralize harmful free radicals. Free radicals are groups of atoms that have at least one unpaired electron and are therefore unstable and highly reactive. In animal tissues, free radicals can damage cells and are believed to accelerate the progression of cancer, cardiovascular disease, and age-related diseases.
Vitamin-like substances
Some substances have not been recognized as vitamins although they in some connections work like such. They are also called vitamin-like substances. Examples are e.g. B10: PABA, B13: orotic acid, B15: pangamic acid, B17: Amygdalin, and the substances Inositol and Choline. Co-enzyme Q10 is also a substance with vitamin-like features.
Other vitamin effects
Some vitamins are antidotes to poisonous substances. Vitamin C is a potent antidote to many substances despite the fact that vitamin C itself is a fragile substance which cannot stand up to heat or sunlight.
Whether a vitamin functions as a vitamin, an antioxidant or an antidote depends on the amounts given. For instance, 10 mg. of vitamin C only protects against the worst symptoms of scurvy such as loose teeth and bleeding skin and entrails.
Vitamin complexes
Vitamins can be used as a therapy in large doses. However, one vitamin should be combined with exactly balanced doses of other vitamins and minerals to avoid creating vitamin imbalances. For this purpose, vitamin complexes or vitamin-mineral complexes can be used with advantage. Firstly, it makes the cure cheaper, secondly, the proportion between the different substances is balanced in these products.
This method consists of taking a basic supplement of all vitamins and minerals and an extra supplement of single vitamins if needed.
Also see "Mulitivitamin-minerals".