Every year antidepressants make roughly $15–17 billion worldwide. Millions of people rely on them. At the same time one of the most effective things for improving mood remains completely free, sunlight.
Our bodies evolved outdoors. Morning light hitting the eyes helps set the circadian clock, which triggers melatonin and the daytime rise in serotonin. It also sparks vitamin D synthesis. Simply spending time outside is associated with lower lifetime risk of depression and less frequent use of antidepressants.
There is a time and place for medical intervention, but research does suggest exposure to natural light is one of the highest effective and lowest cost habits available. Even sitting by a window while working or a short outdoor break at lunch can move the needle for many people.
Much Love, Lynn