Research

Hormonal

Blue light (short-wavelength) is the most effective at resetting the human circadian system and suppressing melatonin.

Prioritize blue light exposure during the day to boost alertness and set your circadian clock. Avoid blue light from screens and bright lights in the evening to protect melatonin production.

StrongSupportsVERY_HIGH confidence
circadian phase resetting and melatonin suppression in response to bright monochromatic light is most sensitive to short-wavelength (blue) light
Charles A. Czeisler et al. · Cold Spring Harbor Symposia on Quantitative Biology · 2007

Why this rating

Based on studies with monochromatic light and blind individuals.

Source

Sleep and Circadian Rhythms in Humans

Charles A. Czeisler et al. · Cold Spring Harbor Symposia on Quantitative Biology · 2007

DOI 10.1101/sqb.2007.72.064

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DOI resolved against Crossref · corpus check 2026-06-10

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