Energy use is central to human society and provides many health benefits. But each source of energy entails some health risks. This article reviews the health impacts of each major source of energy, focusing on those with major implications for the burden of disease globally. The biggest health impacts accrue to the harvesting and burning of solid fuels, coal and biomass, mainly in the form of occupational health risks and household and general ambient air pollution. Lack of access to clean fuels and electricity in the world's poor households is a particularly serious risk for health. Although energy efficiency brings many benefits, it also entails some health risks, as do renewable energy systems, if not managed carefully. We do not review health impacts of climate change itself, which are due mostly to climate-altering pollutants from energy systems, but do discuss the potential for achieving near-term health cobenefits by reducing certain climate-related emissions.