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Light TherapyEvidence & Dosage

10,000-lux daylight lamp — SAD, jet lag, shift work.

Evidence at a glance

Total studies
442
With abstract
45
Meta / Systematic / RCT
16
Highly cited
13
Publication years
1992–2026

Light Therapy 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 Light Therapy

Ranked by influential-citation count and publication year.

  1. The effects of light therapy on sleep problems: A systematic review and meta-analysis.

    Sleep Med Rev2016n=115meta128 influential citations

    Although bright light therapy seems a promising treatment for sleep problems, research shows inconclusive results. This meta-analysis is the first to systematically review the effect of light therapy on sleep problems in general and on…

  2. Effect of phototherapy (low-level laser therapy and light-emitting diode therapy) on exercise performance and markers of exercise recovery: a systematic review with meta-analysis.

    Lasers Med Sci2015Meta-Analysis98 influential citations

    Recent studies have explored if phototherapy with low-level laser therapy (LLLT) or narrow-band light-emitting diode therapy (LEDT) can modulate activity-induced skeletal muscle fatigue or subsequently protect against muscle injury. We…

  3. Blue light phototherapy in the treatment of acne.

    Photodermatol Photoimmunol Photomed2004n=31RCT36 influential citations

    <h4>Background</h4>Blue light irradiation is known to be effective against acne. However, the profile of a good candidate is still unclear.<h4>Methods</h4>Thirty-one Taiwanese with symmetrical facial acne were irradiated with blue light on…

  4. Blue-Light Therapy for Seasonal and Non-Seasonal Depression: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    Can J Psychiatry2022n=347Meta-Analysis28 influential citations

    Objectives To determine the efficacy and safety of blue-light therapy in seasonal and non-seasonal major depressive disorder (MDD), by comparison to active and inactive control conditions. Methods We searched Web of Science, EMBASE,…

  5. The Effects of Light Therapy on Sleep, Depression, Neuropsychiatric Behaviors, and Cognition Among People Living With Dementia: A Meta-Analysis of Randomized Controlled Trials.

    Am J Geriatr Psychiatry2024n=1,074Meta-Analysis24 influential citations

    <h4>Objective</h4>Alterations in the suprachiasmatic nucleus due to underlying pathologies disrupt the circadian rhythms in people living with dementia (PLWD). Circadian rhythms significantly impact sleep, emotional, and cognitive…

  6. Light therapies for acne: abridged Cochrane systematic review including GRADE assessments.

    Br J Dermatol2018n=4,211Meta-Analysis22 influential citations

    We undertook a Cochrane review of randomized controlled trials (RCTs) evaluating the effects of light-based interventions for acne vulgaris. We searched the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, ISI Web of…

  7. Adjunctive bright light therapy for treating bipolar depression: A systematic review and meta-analysis of randomized controlled trials.

    Brain Behav2020n=190Meta-Analysis20 influential citations

    Objectives Bright light therapy (BLT) was reported as an effective adjunctive treatment option for bipolar disorder. Previous meta‐analytic study showed that augmentation treatment with light therapy significantly decreased the severity of…

  8. Clinical outcomes of light therapy in hospitalized patients - A systematic review.

    Chronobiol Int2022n=29Systematic Review20 influential citations

    Light therapy and the effects on biological function have been known and investigated for decades. Light therapy is used to compensate for the lack of exposure to sunlight, which is thought to be linked to major depressive disorder with…

  9. Evaluation of self-treatment of mild-to-moderate facial acne with a blue light treatment system.

    J Drugs Dermatol2011n=33Clinical Trial16 influential citations

    <h4>Introduction</h4>This study evaluated the efficacy and tolerability of treating mild-to-moderate facial acne using a new, hand-held, light-emitting diode blue light device in conjunction with a foam cleanser containing 5% glycolic acid…

  10. Circadian light therapy and light dose for depressed young people: a systematic review and meta-analysis.

    Front Public Health2023n=1,031Meta-Analysis10 influential citations

    Background Empirical evidence has shown that light therapy (LT) can reduce depression symptoms by stimulating circadian rhythms. However, there is skepticism and inconclusive results, along with confusion regarding dosing. The purpose of…

Frequently asked

What dosage was studied?
• Light therapy (Bright light therapy; intensity varied across included studies) • Blue light irradiation on one randomly selected side of the face (Twice weekly for 4 consecutive weeks (8 sessions total))
Which population does the evidence apply to?
Most studies investigated: unknown.
Are there safety considerations for Light Therapy?
• Not reported • Nodulocystic lesions tended to worsen despite blue light treatment. • 3 of 8 naturalistic light trials reported adverse outcomes. • One adverse outcome occurred in the standard light regime comparator.

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