SynthesisPloS one2023
Laughter as medicine: A systematic review and meta-analysis of interventional studies evaluating the impact of spontaneous laughter on cortisol levels.
Synthesis in PloS one, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
What it found
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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
9 citing papers in PubMed.
- The effect of laughter yoga on well-being, perceived stress, and academic self-efficacy in nursing students: A randomized controlled trial.Applied psychology. Health and well-being · 2025Trial
- Clowning in care: long-term effectiveness of clown visits on residents' affect, resilience, sleep quality and functionality.BMC geriatrics · 2026Article
- Humour as emotion regulation and resource in autism: a narrative review.Frontiers in psychiatry · 2026Review
- The Potential of a Robot Presence in Close Relationship to Influence Human Responses to Experimental Pain.Life (Basel, Switzerland) · 2025Article
- Smile at work to achieve the level of comfort in the workplace.Industrial health · 2025Article
- Healing Hearts with Humor: The Potential of Laughter Therapy in Cardiac Rehabilitation.Arquivos brasileiros de cardiologia · 2025Article
- Recognition of emotions in German laughter across cultures.Scientific reports · 2024Article
- The relation between humor styles and nurse burnout: a cross-sectional study in China.Frontiers in public health · 2024Article
- The success elements of humor use in workplace leadership: A proposed framework with cognitive and emotional competencies.PloS one · 2024Article
Corrections and comments
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Authors and funding
2 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectivesLaughter as an expression of humor has been recognized as good medicine for centuries. The health benefits of humor-induced well-being remain unclear and thus we conducted a systematic review and meta-analysis of interventional studies to evaluate the impact of spontaneous laughter on stress response as measured by cortisol levels.
designSystematic review and meta-analysis. DATA SOURCES: MEDLINE/PubMed, EMBASE, PsycINFO, Scopus, and Clinicaltrials.gov. ELIGIBILITY CRITERIA: Interventional studies, which could be either randomized placebo-controlled trials (RCTs) or quasi-experimental studies, conducted in adults that compared any spontaneous laughter intervention to a controlled setting and reported changes in cortisol levels were selected. DATA EXTRACTION AND SYNTHESIS: We examined the impact of laughter on percentage change in cortisol levels by calculating pooled estimates of the absolute differences between arithmetic means before and after interventions as compared to control using random-effects model.
resultsEight studies (315 participants; mean age 38.6) met our inclusion criteria; four were RCTs and four were quasi-experiment studies. Five studies evaluated the impact of watching a humor/comedy video, two studies evaluating laughter sessions administered by a trained laughter therapist, and one study evaluating a self-administered laughter program. Pooling these data showed a significant reduction in cortisol levels by 31.9% (95%CI -47.7% to -16.3%) induced by laughter intervention compared to control group with no evidence of publication bias (P = 0.66). Sensitivity analyses demonstrated that even a single laughter session induced a significant reduction of 36.7% in cortisol (95%CI -52.5% to -20.8%). In addition, analyses including the four RCTs reinforced these results by demonstrating a significant reduction in cortisol levels promoted by laughter as compared to the placebo arm [-37.2% (95%CI -56.3% to -18.1%)].
conclusionsCurrent evidence demonstrates that spontaneous laughter is associated with greater reduction in cortisol levels as compared with usual activities, suggesting laughter as a potential adjunctive medical therapy to improve well-being.
trial registrationRegistration number: CRD42021267972.
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