The strict definition of a Vitamin is a compound that is essential, one that we are not able to make in our body, thus must consume in the diet. In the past there have been a number of other molecules classed as vitamins using F, G, H, M and P to denote them.
However, there is no longer a comprehensive alphabet of vitamins. Some letters are used to denote other micronutrients such as minerals.
Where did it start?
At the beginning it was incomprehensible that there would be so many vitamins. In 1913, Scientists created a naming system that was based on two groupings; those that were fat soluble, they named the ‘Fat soluble A’ vitamins, and those that were water soluble, referred to as the ‘Water Soluble B’ vitamins. Then from there the vitamins were named in order of discovery either giving a letter or letter and number for identification. When it was discovered that there were many more than expected they had to move on to C, D, E and so forth. Many times a substance thought to be a vitamin was found to be non-essential. When this happened, the letter was passed by and the next one used. In some cases, the first letter for the function of the compound was used. For example, the German word for Coalgulation is Koagulation. Vitamin K’s name comes from this very word. Vitamins K’s primary role is in the clotting of blood. [1].
21st Century Vitamins
Originally the assumption was that each new discovery would get the next available letter, but the system fell to pieces when many of the post-E vitamins were later re-identified as vitamins in the B complex. Also, to throw another spanner in the works German Scientists rebelled and decided to assign letters based on medical relevance rather than order of discovery.
The following is a list of chemicals that had previously been classified as vitamins, as well as the earlier names of those that later became the B vitamins:
- Vitamin F: Known today as the essential fatty acids, including Omega-3 and Omega-6 varieties.
- Vitamin G: The American name for British Vitamin B2. Eventually it was agreed for scientific accuracy there should be one name, we now refer to it as Riboflavin.
- Vitamins H: H is one that got named under the German rule, it stands for ‘Haut’, German for skin. It came from it’s medical use in which it’s thought to aid and strengthen. It’s now called B7 or Biotin.
- Vitamin I was said to have a role in digestion, and has since been identified with various members of the B complex group.
- Vitamin J: Didn’t make the cut as it was discovered to be beneficial to guinea pigs but unecessary for humans.
The second half of the alphabet gets even messier: the bulk of the later would-be vitamins proved not to be significant in human growth and consequently were stripped of their title.
- Vitamin L, so named for for its primary role in rat lactation. Better known as Anthranilic acid. L1 is now closely regulated by the DEA: as one of the primary compounds is irresponsibly used by humans as a powerful recreational sedative. It falls into that intriguing category of substances that are potentially fatal.
- Vitamin M is now called Folic acid or B9;
- Vitamin N is thought to have been Thioctic acid/Alpha Lipoic Acid, as it was said to help ‘burning mouth syndrome’.
- Vitamin O was the original name for Carnitine, an amino acid.
- Vitamin P was a name given to the compounds called Flavonoids, which has been clinically proven to contribute more to the pigmentation of plants than to any matter of human well-being.
- Vitamin Q is an antioxidant called Coenzyme Q or otherwise written as Q10.
- Vitamins R, S, T, U, V, W, X, Y and Z either turned out to be inessential to human health (Vitamin S is thought to contribute to the growth of chicks and Vitamin T heals insect wounds) and thus failed to clear the vitamin threshold, or never existed [2].
- https://www.quora.com/How-come-there-are-no-vitamins-F-G-H-I-or-J-but-there-is-a-well-known-vitamin-K
- Cecil Adams, Why Does Vitamin K Exist, But Not Vitamin H? http://www.washingtoncitypaper.com/columns/straight-dope/article/13046516/why-does-vitamin-k-exist-but-not-vitamin-h-and