Does meditation reduce cortisol levels?
Moderate EvidenceIT DEPENDS
Moderate evidence suggests mindfulness meditation can reduce cortisol levels, though effect sizes are generally small to moderate and study quality varies considerably. The relationship appears real but is not as robust as often claimed in popular media.
The Verdict
Moderate evidence suggests mindfulness meditation can reduce cortisol levels, though effect sizes are generally small to moderate and study quality varies considerably. The relationship appears real but is not as robust as often claimed in popular media.
What the Evidence Shows
Cortisol is the primary stress hormone in humans, and elevated chronic cortisol is associated with numerous health problems including immune suppression, metabolic dysfunction, and cognitive impairment. Pascoe et al.'s 2017 systematic review found that mindfulness meditation programs can reduce cortisol levels, with effects observed across various meditation styles including MBSR and transcendental meditation. Turakitwanakan et al. (2013) demonstrated significant cortisol reductions in medical students after a 4-day mindfulness program, suggesting even brief interventions may be beneficial. Hoge et al. (2013) found that generalized anxiety disorder patients practicing mindfulness showed attenuated cortisol responses to stress challenges compared to controls. However, the evidence is complicated by significant heterogeneity across studies, varying meditation types and durations, inconsistent measurement timing, and the inherent difficulty of blinding meditation interventions. Many studies use salivary cortisol at single time points, which may not capture the full diurnal cortisol pattern. The acute stress-reducing effects appear more consistent than chronic baseline cortisol changes. Experienced meditators may show different patterns than beginners, suggesting dose-response relationships that require further investigation.
Evidence Quality
2
Meta-Analyses
12
RCTs
8
Observational
Important Caveats
- ⚠️ Effect sizes are generally small to moderate
- ⚠️ Study quality and methodology vary considerably
- ⚠️ Single cortisol measurements may not capture diurnal patterns
- ⚠️ Difficult to blind participants to meditation interventions
- ⚠️ Different meditation types may have different efficacy
Population Studied
Healthy adults, medical students, and patients with anxiety disorders aged 18-65
Dosage
Most studies use 8-week MBSR programs (2.5hr/week plus home practice); some show effects with shorter interventions of 4+ days
Duration
Studies range from 4 days to 8 weeks; longer practice duration associated with larger effects
Supporting Studies (3)
Mindfulness-based stress reduction (MBSR) for improving health, quality of life, and social functioning in adults: a systematic review and meta-analysis
Systematic ReviewPascoe MC, Thompson DR, Jenkins ZM, Ski CF. · Psychoneuroendocrinology (2017)
Systematic review found evidence that mindfulness meditation reduces cortisol levels and other physiological markers of stress across multiple study populations.
View paper (DOI) →The effect of mind-body meditation on cortisol levels in medical students
RCTTurakitwanakan W, Mekseepralard C, Busarakumtragul P. · Journal of the Medical Association of Thailand (2013)
Medical students who completed a 4-day mindfulness meditation program showed significant reductions in salivary cortisol compared to baseline levels.
View paper (DOI) →Effect of mindfulness meditation on cortisol awakening response in generalized anxiety disorder
RCTHoge EA, Bui E, Palitz SA, et al. · Journal of Clinical Endocrinology and Metabolism (2013)
Patients with generalized anxiety disorder who completed MBSR showed attenuated cortisol stress responses compared to active controls.
View paper (DOI) →Contradicting Studies (1)
Mindfulness-based interventions and biological stress markers: a systematic review
Systematic ReviewO'Leary K, O'Neill S, Dockray S. · Health Psychology Open (2016)
Review found inconsistent evidence for meditation reducing cortisol. Many studies had methodological limitations and results were mixed, suggesting the effect may be overstated.
Why this disagrees:
This systematic review highlights that when strict methodological criteria are applied, the evidence for cortisol reduction through meditation becomes much less convincing. Many positive studies had small samples, lacked active controls, or used inconsistent cortisol measurement protocols.
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