Around 12 months ago the medical community came out with the news that fat wasn't really that bad for you, and that sugar was the real killer.
Someone born 30 years ago would have had, throughout their entire life, a non-stop, 24/7, barrage of messages, advice, from every perceivable source, that saturated fats were the evil that will kill you.
By all means have a good laugh at someone who is a little , let's say 'eccentric'. But to accept at face value all those zeitgeist proclamations, is taking the easy option..