A Fitness Trainer is not a good analogy either, because you can't stay in business long as a fitness trainer if you have no idea of the basics of fitness or anatomy. E.g. a fitness trainer who said that you breath through your feet, so you should wear sandals when running knows as much about biology as a nutritionist who thinks chlorophyll can oxygenate your blood. However the magic super food nutritionist had a prime time TV show! High ranking, popular nutritionists can believe things that are nonsense, what hope do you have about a local nutritionist?