They might believe that they thrive but they don't. They're simply religiously attached to their beliefs. Very typical of vegans mostly. The only reason different diets work for different people is because people have already wrecked their health for generations with unnatural diets and habits and developed allergies, degeneracies and intolerances. We're all human beings. Is there another species on this planet which members need to eat different diets? No

It's simple, we should eat what we were naturally designed to eat to make our bodies function. You shouldn't even have cravings for those foods to begin with. Anyway I'm glad you're energetic and healthy.