So.
There did used to be a bunch more “vitamins”, but they were later determined to be other kinds of materials.
A know some vitamins were demoted because we discovered that they were made inside the body.
Real captain are in the comments.
Thanks for the link!
This I understand, but why so many 'B’s? Are these also former vitamins that we discovered were just variations of the original B vitamin?
Back in the day, vitamins were discovered by observing the effects of not consuming certain foods. They observed two types: Fat soluble A, and water soluble B.
Then, as they started discovering the actual chemicals responsible, we got the various B vitamins.
Some were dropped because we discovered the body actually makes it on its own, and some were given different letters because their function was very different from the rest.