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Blue LightEvidence & Dosage

Screen spectrum suppresses melatonin — filters, glasses, incandescent bulbs.

Studies last updated

Evidence at a glance

Total studies
1,000
With abstract
49
Meta / Systematic / RCT
128
Highly cited
50
Publication years
1979–2026

Blue Light in the context of Methods

This topic is part of our "Methods" world. There you'll find methodology, evidence and the highest-impact levers — plus the order in which they sensibly build on each other.

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Top studies on Blue Light

Ranked by influential-citation count and publication year.

  1. Sensitivity of the human circadian pacemaker to nocturnal light: melatonin phase resetting and suppression.

    J Physiol2000Clinical Trial200 influential citations

    Ocular exposure to early morning room light can significantly advance the timing of the human circadian pacemaker. The resetting response to such light has a non-linear relationship to illuminance. The dose-response relationship of the…

  2. Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness.

    Proc Natl Acad Sci U S A2015clinical200 influential citations

    In the past 50 y, there has been a decline in average sleep duration and quality, with adverse consequences on general health. A representative survey of 1,508 American adults recently revealed that 90% of Americans used some type of…

  3. A meta-analysis of biological impacts of artificial light at night.

    Nat Ecol Evol2021Meta-Analysis191 influential citations

    Natural light cycles are being eroded over large areas of the globe by the direct emissions and sky brightening that result from sources of artificial night-time light. This is predicted to affect wild organisms, particularly because of…

  4. Systematic review of light exposure impact on human circadian rhythm.

    Chronobiol Int2019n=128systematic173 influential citations

    Light is necessary for life, and artificial light improves visual performance and safety, but there is an increasing concern of the potential health and environmental impacts of light. Findings from a number of studies suggest that…

  5. Light Environment of Arctic Solstices is Coupled With Melatonin Phase-Amplitude Changes and Decline of Metabolic Health.

    Journal of pineal research2025n=62E91 influential citations

    Light environment in the Arctic differs widely with the seasons. Studies of relationships between objectively measured circadian phase and amplitude of light exposure and melatonin in community-dwelling Arctic residents are lacking. This…

  6. Non-visual effects of light on melatonin, alertness and cognitive performance: can blue-enriched light keep us alert?

    PLoS One2011Clinical Trial90 influential citations

    <h4>Background</h4>Light exposure can cascade numerous effects on the human circadian process via the non-imaging forming system, whose spectral relevance is highest in the short-wavelength range. Here we investigated if commercially…

  7. Blue-light filtering spectacle lenses for visual performance, sleep, and macular health in adults.

    Cochrane Database Syst Rev2023n=17Systematic Review87 influential citations

    <h4>Background</h4>'Blue-light filtering', or 'blue-light blocking', spectacle lenses filter ultraviolet radiation and varying portions of short-wavelength visible light from reaching the eye. Various blue-light filtering lenses are…

  8. The circadian basis of winter depression.

    Proc Natl Acad Sci U S A2006Clinical Trial84 influential citations

    The following test of the circadian phase-shift hypothesis for patients with winter depression (seasonal affective disorder, or SAD) uses low-dose melatonin administration in the morning or afternoon/evening to induce phase delays or phase…

  9. Phase-shifting effects of bright morning light as treatment for delayed sleep phase syndrome.

    Sleep1990n=20RCT79 influential citations

    Bright light has recently been shown to have phase-shifting effects on human circadian rhythms. In this study we applied this effect to 20 patients with delayed sleep phase syndrome (DSPS) who were unable to fall asleep at conventional…

  10. Blue-enriched white light in the workplace improves self-reported alertness, performance and sleep quality.

    Scand J Work Environ Health2008n=94Clinical Trial77 influential citations

    <h4>Objectives</h4>Specifications and standards for lighting installations in occupational settings are based on the spectral sensitivity of the classical visual system and do not take into account the recently discovered melanopsin-based,…

Frequently asked

What dosage was studied?
• Evening reading of an electronic book on a light-emitting device (LE-eBook) (Evening exposure; duration not reported in abstract)
Which population does the evidence apply to?
Most studies investigated: unknown.
Are there safety considerations for Blue Light?
• Evening LE-eBook exposure delayed circadian timing. • Evening LE-eBook exposure reduced next-morning alertness. • Evening LE-eBook exposure acutely suppressed melatonin. • Not reported in the abstract.

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