A physician probably learns the physiology of sweat glands, mechanisms for how the human body regulates sodium and potassium, and diseases caused by regulatory mechanisms not working. Unless they had an interest or read a study, I’m not sure I would expect a physician to know that, and in my experience a lot of physicians are reluctant to speculate.

Nutritionists and fitness coaches are much more willing to speculate in my experience, with the caveat that they may not have the same education as a scientist as a physician does.