Try this: Light therapy
- Reviewed by Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing
Seasonal affective disorder (SAD) is a type of depression that typically begins during the late fall and early winter months, when daylight hours are fewer and sunlight exposure decreases. Sunlight stimulates the hypothalamus, a part of the brain that helps control your circadian rhythm — the body’s internal 24-hour sleep-wake clock. Lack of light can throw off your circadian rhythm and cause the brain to produce too much of the sleep hormone melatonin and reduce serotonin, the feel-good brain chemical that affects mood. The result: you feel low and lethargic.
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About the Author
Matthew Solan, Executive Editor, Harvard Men's Health Watch
About the Reviewer
Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing
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