NCCIH. (n.d.). Seasonal Affective Disorder and Complementary Health Approaches : What the Science Says. [online] Available at: https://www.nccih.nih.gov/health/providers/digest/seasonal-affective-disorder-and-complementary-health-approaches-science [Accessed 17 Nov. 2020].
Abstract: There is some evidence that light therapy may be useful as a preventive treatment for people with a history of season affect disorder. The idea behind light therapy is to replace the diminished sunshine of the fall and winter months using daily exposure to a light box. Most typically, light boxes filter out the ultraviolet rays and require 20-60 minutes of exposure to 10,000 lux of cool-white fluorescent light, an amount that is about 20 times greater than ordinary indoor lighting.