I have suspected this for a long time as well; by requiring attention and planning to get the appropriate items from the limited set permitted by the diet the r

I have suspected this for a long time as well; by requiring attention and planning to get the appropriate items from the limited set permitted by the diet the real goal, making an evaluation each time you eat, is achieved. I suspect people cycle through different palettes/diets until they find one that suits their personal tastes, or until some other stars align in their life and motivation such that their next attempt was going to succeed anyway. People then become cargo cult evangelists for that particular diet. That's without even looking at some of the people who profit from diet fads and promote them with various techniques. That's all conjectural on my part though, perhaps one day a researcher that models memes with techniques from epidemiology will get an appropriate data set to seriously investigate.