Objectives. To quantify the increased disease burden caused by US health care sector life cycle greenhouse gas (GHG) emissions of 614 million metric tons of carbon dioxide equivalents in 2013. Methods. We screened for health damage factors that linked GHG emissions to disease burdens. We selected 5 factors, based on appropriate temporal modeling scales, which reflect a range of possible GHG emissions scenarios. We applied these factors to health care sector emissions. Results. We projected that annual GHG emissions associated with health care in the United States would cause 123 000 to 381 000 disability-adjusted life-years in future health damages, with malnutrition being the largest damage category. Conclusions. Through their contribution to global climate change, GHG emissions will negatively affect public health because of an increased prevalence of extreme weather, flooding, vector-borne disease, and other effects. As the stewards of global health, it is important for health care professionals to recognize the magnitude of GHG emissions associated with health care itself, and the severity of associated health damages.