Having a working, practical definition of what a disease is can help when trying to decide whether this-or-that thing is a disease, or when using the term “disease” in communication.
The definition I use for the term disease is criteria-based. The criteria I use are:
- An impairment of the normal functioning of some aspect of the body;
- Characteristics signs and symptoms;
- Harm or morbidity.
(This serves me as a practical definition, but I would point out a theoretical definition of what a disease is would require the agreement of what the definition is of “definition.”)
(REF: AACE Obesity Position Statement, Endocr Pract. 2012;18(No. 5))