Having spent nearly a decade in the "nutrition scene" I can tell you that there are some disturbing trends among those espousing different ways of eating:
The Flip Flop: A faulty dietary paradigm allows a food to be labeled a "toxin" one month, and benign another.
The Disease Causing Macronutrient: While few hold the idea that any one specific macronutrient causes disease, many subscribe to the paradigm that too much of a macronutrient (especially carbohydrate) absolutely does cause disease.
The "Evolutionary" Paradigm
Ancestral diets are great starting places, but have lead to some questionable therapies over the years. Speculating about the metabolic conditions of our ancestors leads to unanswerable questions, wild speculation, and dead ends.
The Real Food Paradigm
Consuming a diet of real food is a great starting place. However, this way of eating may or may not address specific concerns the user has about conquering stress, increasing virility, overcoming depression, and improving digestion.
The Moral Paradigm
Ideas of morality often get intertwined with different ways of eating. While people are free to consume whatever they wish, when facing specific issues "morals" are best kept away from your mouth.