Some of these nutrients can be produced by the body through its natural chemical processes, and some must be obtained from food.
Whatever the body can produce on its own are called nonessential nutrients, and whatever must be consumed through food are called essential nutrients.
Vitamins are one of the sevenCarbohydrates, proteins, lipids, water, vitamins, minerals, and fibre. essential nutrients, i.e. the body doesn’t produce them or produces inadequate quantities of them.
Another characteristic of a vitamin is that the body requires it in small quantities.
Now, the first five vitamins, A, B, C, D, E, got their sequential names because they were discovered one after the other in the early 1900s.
They were discovered because of the various diseases that their deficiencies caused.
It was a given in the health-science community that as more vitamins were discovered, they would get the next available letters.
But as new vitamins were discovered, they were found to A) not meet the criteria or B) be very closely related in chemical structure to some other vitamin.
So, they ended up as numbered variants of that vitamin (with which it shared the structure) instead of being labelled as separate vitamins.
E.g., Vitamin F was found to be an essential nutrient, but the body required it in substantial quantities, so it didn’t fit the ‘required in small quantities’ criterion of vitamins.
So, Vitamin F became fatty acids of Omega-3 and Omega-6 varieties.
Vitamin G, H & M were found to be closely related in chemical structure to Vitamin B.
So, they became numbered variants of Vitamin B — B2 (riboflavin), B7 (biotin), and B9 (Folic acid), respectively.
There is no record of vitamin I, but some experts believe it is identified with other members of the Vitamin B group.
Vitamin J (some call in choline and others call it a combination of B2 and nonessential catechol) was found to be missing a chemical structure criterionIt doesn’t function like a coenzyme.
