you might want to see a specialist for something that you know is specifically is wrong with your body such as your having sight problems or hearing issues. You would see a primary care if you are just feeling sick or are hurting and you need a diagnosis to find out
A balanced diet, one that includes carbohydrates, proteins, and fats is necessary to slow down digestion. Each plays a different role when it comes to metabolism and energy use. Fats are necessary for the long runs as they are your primary fuel source when carbs run out , carbs are necessary for the medium length runs when your phosphocreatine runs out. Proteins are necessary for recovery. An Adequate ingestion of all the macros post workout, permits recovery for next day training. When it comes to digestion, a mixed meal including all macros slows down digestion and allows the absorption of all nutrients.
I would say when all three dont match people rely on body language for an honest answer. so a i hope it helps..