Refer to 15943 for full description that was split into 3 parts (hence this new tracker item) for each component. The use case is the ability or order a specific dietary item (nutrient). Nutrition order is modeled as the ability to order full diet. In the use case, the intent is to require a breast milk only diet for a newborn and assure the only nutrient is breast milk (which means water not allowed either). Other use cases include the ability to order a specific nutrient in addition to the "diet." The current modeling does not allow this capability - it is more consistent with MedicationRequest.