Functional medicine is a form of alternative medicine that encompasses a number of unproven and disproven methods and treatments. Its proponents claim that it focuses on the “root causes” of diseases based on interactions between the environment and the gastrointestinal, endocrine, and immune systems to develop “individualized treatment plans”. It has been described as pseudoscience, quackery, and at its essence a rebranding of complementary and alternative medicine.
In the US, functional medicine practices have been ruled ineligible for course credits by the American Academy of Family Physicians because it considers they may be “harmful” and “dangerous”.
The discipline of functional medicine is vaguely defined by its proponents. Oncologist David Gorski has written that the vagueness is a deliberate tactic which facilitates the discipline’s promotion, but that in general it centers on unnecessary and expensive testing procedures performed in the name of “holistic” health care.
Proponents of functional medicine oppose established medical knowledge and reject its models, instead adopting a model of disease based on the notion of “antecedents”, “triggers”, and “mediators”. These are meant to correspond to the underlying causes, the immediate causes, and the particular characteristics of a person’s illness respectively. A functional medicine practitioner will devise a “matrix” from these things which acts as a basis for treatment.
Treatments, practices, and concepts will generally be those not supported by medical evidence.