What Are SAD Lamps and How Do They Work? Seasonal Affective Disorder (SAD) lamps, also known as light therapy boxes, are specially designed devices that mimic natural outdoor light. These lamps are used to help alleviate symptoms of seasonal affective disorder and other types of depression related to light deprivation. SAD lamps work by emitting a bright light that stimulates the body’s circadian rhythms and suppresses the natural release of melatonin. The light from SAD lamps is much brighter than regular indoor lighting, typically ranging from 2,500 to 10,000 lux (a measure of light intensity). For comparison, a bright sunny...