Drawing a Line Between Integrative and Functional Medicine.

Integrative Medicine (IM) and Functional Medicine (FM) are frequently conflated but represent fundamentally different models of care. IM is an academic discipline grounded in evidence-based medicine, whole-person care, and interdisciplinary collaboration, incorporating evidence-informed complementary, traditional, and Indigenous healing practices within conventional standards of diagnosis and management. FM is a distinct clinical model built on the premise that chronic disease reflects disturbances in biological function, seeking individualized "root causes" through systems-based assessment, specialized diagnostic constructs, and nonstandard laboratory testing. Although many interventions used in FM, including nutrition, exercise, sleep, and stress management, are evidence based, evidence validating FM as a distinct diagnostic and therapeutic model remains limited. FM diagnostic strategies may contribute to low-value testing, care cascades, and health inequities through substantial out-of-pocket costs. Using the tripartite mission of academic medicine-education, research, and clinical care-we compare these models and argue that new clinical frameworks should meet the same standards of evidence and clinical validity expected throughout medicine.