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Evening Darkness
Dimming the lights
Overview
Reducing light intensity and blue-light exposure in the 2 hours before bed. The brain uses light as the single strongest signal for whether it is day or night.
How it works
Lack of blue light signals the suprachiasmatic nucleus that it is night. Evening melatonin release is the biological "lights out" cue.
Benefits
Melatonin: allows the natural evening rise instead of suppressing it.
A
Protocol
- 1Dim overhead lights 2 hours before bed.
- 2Switch devices to night mode or use amber-tinted glasses.
- 3Use low, warm bedside lamps instead of ceiling lights.
Safety Profile
Research Summary
Blue light (460–480 nm) suppresses melatonin significantly more than other wavelengths. Brainard et al. and others have mapped the action spectrum.
Sources
Last updated: 2026-04-10
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Medical Disclaimer
This is a research summary, not medical advice. Body Signals is an independent research digest — it summarises published research for informational purposes and is not a healthcare provider. Supplements like melatonin, valerian, and magnesium can interact with prescription medications — check with your doctor or pharmacist before starting any supplement. Chronic insomnia may indicate an underlying condition (sleep apnoea, thyroid dysfunction, depression) and warrants a medical evaluation.
Need professional guidance?
If sleep issues persist despite lifestyle changes, a sleep specialist or your family doctor can help rule out underlying conditions.
Learn about sleep specialists