I don't know what there are more of - fashion fads or diet fads. In just the last few weeks I've heard of diets where you count your bites, or you only need to exercise for 1 minute each day, and now another new diet for 2015 - don't eat after 4pm.
I am not a super healthy person - but I am not overweight. I go to the gym once in a while or do some push ups at home. My wife on the other hand is crazy fit! She goes to the gym 4 or 5 times a week and eats healthy too. But even she isn't into Crossfit.