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Morning LightEvidence & Dosage

Bright light in the first hour — cortisol, the melatonin rhythm.

Evidence at a glance

Total studies
268
With abstract
50
Meta / Systematic / RCT
5
Highly cited
50
Publication years
1986–2026

Morning 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 Morning Light

Ranked by influential-citation count and publication year.

  1. 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…

  2. 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…

  3. Chronotherapeutics (light and wake therapy) in affective disorders.

    Psychological medicine200555 influential citations

    The Committee on Chronotherapeutics, delegated by the International Society for Affective Disorders (ISAD), makes the following recommendations after reviewing the evidence as of November 2004. (1) Wake therapy is the most rapid…

  4. Light therapy for non-seasonal depression.

    The Cochrane database of systematic reviews200447 influential citations

    <h4>Background</h4>Efficacy of light therapy for non-seasonal depression has been studied without any consensus on its efficacy.<h4>Objectives</h4>To evaluate clinical effects of bright light therapy in comparison to the inactive placebo…

  5. A randomized, double-blind, placebo-controlled study of light therapy for antepartum depression.

    The Journal of clinical psychiatry2011n=1646 influential citations

    <h4>Objective</h4>Affective disorder during pregnancy is a common condition requiring careful judgment to treat the depression while minimizing risk to the fetus. Following up on promising pilot trials, we studied the efficacy of light…

  6. Effect of morning bright light treatment for rest-activity disruption in institutionalized patients with severe Alzheimer's disease.

    International psychogeriatrics2005n=4637 influential citations

    <h4>Background</h4>Disturbances in rest-activity rhythm are prominent and disabling symptoms in Alzheimer's disease (AD). Nighttime sleep is severely fragmented and daytime activity is disrupted by multiple napping episodes. In most…

  7. A randomized, controlled trial of bright light therapy for agitated behaviors in dementia patients residing in long-term care.

    International journal of geriatric psychiatry1999n=1536 influential citations

    <h4>Background</h4>Agitated behaviors are common in dementia patients residing in chronic care settings. Their occurrence may be associated with lack of adequate exposure to sunlight and with circadian rhythm…

  8. Randomized clinical trial of bright light therapy for antepartum depression: preliminary findings.

    The Journal of clinical psychiatry200434 influential citations

    <h4>Background</h4>Bright light therapy was shown to be a promising treatment for depression during pregnancy in a recent open-label study. In an extension of this work, we report findings from a double-blind placebo-controlled pilot…

  9. Dawn-dusk simulation light therapy of disturbed circadian rest-activity cycles in demented elderly.

    Experimental gerontology2003n=1333 influential citations

    We investigated whether low intensity dawn-dusk simulation (DDS), a 'naturalistic' form of light therapy designed to embed sleep in its accustomed phase, could improve the disturbed circadian rest-activity cycle, nocturnal sleep and and/or…

  10. Light treatment prevents fatigue in women undergoing chemotherapy for breast cancer.

    Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer2012n=5833 influential citations

    <h4>Purpose</h4>Fatigue is one of the most disturbing complaints of cancer patients and is often the reason for discontinuing treatment. This randomized controlled study tested the hypothesis that increased morning bright light, compared…

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 Morning Light?
• Evening LE-eBook exposure delayed circadian timing. • Evening LE-eBook exposure reduced next-morning alertness. • Evening LE-eBook exposure acutely suppressed melatonin.

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