By definition, a medical food is formulated to be consumed or administered orally under the supervision of a healthcare practitioner for the dietary management of a specified condition. As with an elemental diet, it is intended for the specific dietary management of a condition for which distinctive nutritional requirements are needed, and based on scientific principles established by medical evaluation. A medical food is distinguishable from a broader category of foods for special dietary uses.

To meet the criteria, a medical food must be a food for oral or tube feeding, be labeled appropriately for the medical condition, intended for use under medical supervision, and be specially formulated and processed for patients.

A medical food is NOT a dietary supplement or all foods which feed ill patients. When properly designed, commercial elemental diet products are medical foods.