Cailin Heinze,a veterinary nutritionist at Cummings Veterinary Medical middle, respondsVeterinarians must prescribe certain therapeutic diets because, or depending on the disease being addressed,these foods may contain levels of nutrients below what is legally allowed to be sold for a healthy pet without that medical condition. whether a pet has a health issue that warrants a special diet, it should be closely monitored by a veterinarian, and even whether that diet contains nutrient levels safe for healthy pets.
Source: tufts.edu