This Gillian McKeith ?
She had never made wild, fanciful claims. Just by casually adopting (then more seriously) adopting her suggestions, Mr. Peel, a heavy diabetic has gone from 5 injections of insulin a day to 1. This is just based on diet alone.
I know dozens of people (myself included) who have a degree in one discipline and follow another. In fact, the best employees that I have hired in the past (looking for Computer Science people) had original backgrounds in Japanese Literature, Architecture and Latin. They followed their passion and were excellent in their field. I find your bigotry very narrow minded and distasteful.