On board with your comment until > a real medical professional, nutritionist, fitness trainer, etc Family practitioners also commonly prescribe antidepressant

On board with your comment until > a real medical professional, nutritionist, fitness trainer, etc Family practitioners also commonly prescribe antidepressants and the like. I'd say there is still wild debate about what is a healthy diet. Until recently (and maybe even still) most nutritionists would prescribe something aligning with the Nixon-administration-guided carbohydrate pyramid. Anything a fitness trainer guides you to do is likely less effective than the basics (squats, deadlifts, running). There is substantial B.S. in all of the professions you mention. The least one can do is find the person dishing it in the right realm. If a person has schizophrenia, it still massively behooves them or their family to seek the aid of a psychiatrist. A hot mess of conflicting theory and pseudoscience, yes, but it's all we have.