The Canadian government greeted 2014 with the first tier of its new energy-efficiency standards for light bulbs,1 which will effectively ban incandescent light bulbs by next year.2 But efficient lighting can have its own drawbacks. For instance, although devoid of the mercury used in compact fluorescent lamps (CFLs), some white light-emitting diodes (LEDs) emit a wavelength of light associated with adverse human health effects. In this issue of EHP, researchers study retinal changes in rats exposed to white LEDs like those sometimes used in household lighting.3