Light Therapy (Bright Light Box)

Key points

• 10,000 lux bright light box mimics morning sun — resets the circadian clock when outdoor light is insufficient
• Evidence-based treatment for seasonal affective disorder (SAD) — as effective as antidepressants in head-to-head trials
• Use within 30 minutes of waking, for 20–30 minutes — do not stare directly into the light; angled or beside you is fine
• Also useful for jet lag, shift work, and anyone who wakes before sunrise in winter
• Combines with morning outdoor light — even dim outdoor light provides more circadian signal than indoor light