P4 medicine: the future around the corner.

Traditional medical practice has been "reactive" (doctor takes part when disease appears). The theoretical (scale free networks and complex systems), technological (high efficiency "omic" technologies) and conceptual (biology systems) advances throughout the last decade, allow us to anticipate the transition to an "anticipatory" medicine, based on health (not on disease). This review establishes the conceptual bases and discusses the principal aspects of this new medicine, known as "P4 Medicine" standing for personalized, predictive, preventive and participatory.