Who assigned letters to the particular Vitamins?

Why did they designate more than one B vitamin, instead of continuing with alphabetic letter designations?

Why did they do away with going alphabetical with the vitamin names altogether after Vitamin E?

Seems like this would have been asked and answered before, but I couldn’t find anything in the searches.

Hi, Milo. Start here. http://www.britannica.com Look up “Casimir Funk”. I can’t get the EB to give me an article link, dunno whether it’s them or me. The link stops after the comma and all you get is the EB home page. (Sorry I can’t take more time to talk, but Maury Povich is doing “Teenage Girls Who Dress Too Sexy and Want to be Strippers and are Having Sex with Older Men and are Breaking Their Mothers’ Hearts” and I have to get back.)

Long time no see, DDG. Welcome back.

There are vitamins given letters higher than E. Vitamin K is a real vitamin. The only English letter that has never had at least one putative vitamin named after it is the letter ‘Z’. The subscripts of the B vitamins have run all the way from 1 to 14. A lot of them were later renamed, recognized as not being vitamins, or recognized as not being essential for human health. A lot of the experimentation on vitamins involved testing birds, but the nutritional requirements of birds and humans are not identical. See The Missing Vitamins