Since the 1980s, light therapy has been regularly used in the treatment of seasonal affective disorder. It aims to expose people with SAD to a bright light every day to make up for the lack of natural bright sunshine in the colder months.
For this treatment, the person sits in front of a very bright light box every day for about 30 to 45 minutes, usually first thing in the morning, from fall to spring. The light boxes, which are about 20 times brighter than ordinary indoor light, filter out potentially damaging UV light, making them safe to use. However, people with certain eye diseases or people taking certain medications that increase sensitivity to sunlight may need to use alternative treatments or use light therapy under medical supervision.