Why is complete darkness important for sleep?
Written by
Tran Quang
Reviewed by
Prof. Graham Pierce, Ph.D.Complete darkness is essential for sleep since a small amount of light exposure can inhibit melatonin production up to 50%. This is an important hormone that regulates your sleep cycle and helps control your circadian rhythm. The darkness tells your pineal gland to release melatonin naturally. I personally use blackout curtains and tape over my electronics. That dramatically improved my sleep within just a few days.
Light Source Elimination
- Cover LED indicators with electrical tape
- Install blackout curtains blocking 99% exterior light
- Use sleep masks with contoured nose bridges
Light Spectrum Management
- Use red nightlights below 620 nm wavelength
- Avoid blue/green light above 500 nm
- Install smart bulbs with automatic sunset mode
Different wavelengths of light affect melatonin in varying ways. The blue wavelengths between 450-495 nm suppress melatonin to the greatest extent. In contrast, red lights with wavelengths above 620 nm have little to no effect on melatonin production. To mitigate the effects of artificial light, consider installing smart bulbs that automatically shift to a lower color temperature at dusk. I suggest Philips Hue or similar systems. They will keep the lights dimmed without compromising safety.
Full darkness cuts nighttime awakenings by 40%. It maintains uninterrupted sleep cycles for memory consolidation and tissue: repair. Measure the light in your bedroom with light meters. Find illumination of 5 lux or less. My clients do this with layered solutions.
Read the full article: 10 Science-Backed Ways to Fall Asleep Faster
