Home lighting, blue-light filtering, and their effects on melatonin suppression

Area of Science:

• Lighting technology
• Chronobiology
• Sleep science

Background:

• Evening light exposure, particularly blue light, suppresses melatonin production, negatively impacting sleep quality.
• Different lamp technologies (LED, CFL, incandescent) emit varying light spectra that can affect circadian rhythms.

Purpose of the Study:

• To quantify the melatonin suppression potential of common household lamps.
• To evaluate the effectiveness of tunable CCT lamps and blue-light-filtering lenses as countermeasures against light-induced circadian disruption.

Main Methods:

• Measured light emissions from 52 lamps across LED, CFL, and incandescent technologies.
• Determined Melatonin Suppression Value (MSV), melanopic, and photopic illuminance for each lamp.
• Assessed the impact of tunable CCT LED lamps and various blue-light-filtering lenses on melatonin suppression.

Main Results:

• Cool white LED and CFL lamps exhibited the highest melatonin suppression (median 12.3% and 12.1% MSV, respectively).
• Tunable LED lamps significantly reduced melatonin suppression when set to warm white (2100 K), lowering MSV to 0.1%.
• Only two "brown"-tinted blue-light-filtering lenses effectively reduced melatonin suppression to below 0.3% MSV.

Conclusions:

• Cool white CFL and LED lighting pose a greater risk to sleep physiology compared to incandescent and warm white alternatives.
• Adjusting tunable lamps to warmer settings and utilizing specific "brown"-tinted blue-light-filtering lenses are effective strategies to reduce circadian disruption from artificial lighting.