That love promotes health surprises few people, yet the scientific study of love and physical health is in its infancy. Because love has many facets and is manifested in many ways, as described here, it was banned from Western science, which insisted on observable and simple independent variables. This article presents data indicating the salutary effects of love on physical health. These data are from several areas-psychology, sociology, medicine, epidemiology, and healing-and together form a foundation for understanding and enhancing love and its effects. Three processes are formulated to explain the health-promoting effects of love: psychophysiologic, psychophysical, and psychosocial/behavioral. Love is described as an energy by virtue of its capacity to produce effects.