Cold therapy for major depressive disorder and depressive symptoms
Evidence review
Overview
Two different cold modalities have been studied. Whole-body cryotherapy (WBC: 2-3 minutes of extreme cold air at about -166 to -256 F in a chamber) as an add-on to medication improved depressive symptoms versus a -58 F sham in an RCT of 92 adults with a depressive episode, and in a controlled trial of 60 outpatients (HAM-D response 34.6% vs 2.9%); a 2021 meta-analysis of 10 small studies found a medium between-group effect with high risk of bias, and most WBC studies come from one research group. Cold-water swimming and cold showers have been studied mainly in small uncontrolled studies; a 2026 meta-analysis of 13 studies (4105 participants) found pooled estimates favoring cold-water exposure but with wide confidence intervals and mostly high risk of bias, and its authors concluded benefit is not established. In randomized trials comparing a cold-shower-plus-breathing protocol with slow breathing and warm showers, depressive symptoms improved similarly in both arms. Findings for WBC should not be extrapolated to home cold-water immersion.
Key findings
- WBC sham-controlled RCT in 92 adults with a depressive episode: HAM-D 17 group-by-time interaction p=0.02 vs -58 F sham (Rymaszewska 2020).
- WBC controlled trial, 60 outpatients with depressive and anxiety disorders: HAM-D response 34.6% vs 2.9% and HAM-A response 46.2% vs 0% after 15 sessions added to medication (Rymaszewska 2008).
- WBC uncontrolled series, 30 adults with depressive episode: HAM-D 16.94 to 4.50 after 10 sessions (Rymaszewska 2019).
- WBC meta-analysis, 10 studies, 294 participants: between-group g=0.76 (95% CI 0.17-1.36), high heterogeneity and risk of bias (Doets 2021).
- Cold-water meta-analysis, 13 studies, 4105 participants: pooled estimates favored cold-water exposure for depressive symptoms but CIs were wide and most studies had high or serious risk of bias; authors state benefit is not established (Ngandeu Schepanski 2026).
- RCT, 84 women with high depressive symptoms: cold showers plus fast breathing vs slow breathing plus warm showers produced equivalent reductions (24% depressive symptoms); all 6 dropouts were from the cold-shower arm (Blades 2024).
- Pilot RCT, 141 women with high perceived stress: all four arms improved depressive symptoms by 15.93% with no between-group difference at 3 weeks (Epel 2025).
- Feasibility study in diagnosed depression: 13 recruited, 5 attended regularly; well-being score rose from 39.2 to 54.0 in regular attenders (Hjorth 2023).
Every study we reviewed
2 mixed results · 2 found no effect · 9 found benefit
Each study was checked on PubMed. The colored edge shows the direction of the result. The research library lists 36 studies on depression, across all heat and cold therapies, including case reports and older work not graded here.
Cold-water exposure and psychological outcomes in adults: a systematic review and meta-analysis.
Ngandeu Schepanski S et al. Front Physiol. 2026. PubMed 42819812 · DOI · Free full text
- Who
- adults exposed to cold showers, cold-water immersion or winter swimming (13 studies; randomized, non-randomized, cohort and pre-post designs)
- What
- cold-water exposure of any type (cold shower, immersion, winter swimming)
- Measured
- depressive symptoms, perceived stress, wellbeing, mood, anxiety (Hedges g)
- Result
- Pooled estimates generally favored cold-water exposure for depressive symptoms, perceived stress, wellbeing and mood, but confidence intervals were wide and several estimates attenuated in controlled-only analyses; anxiety showed little evidence of consistent benefit. Authors: evidence does not establish benefit; not a standalone psychiatric treatment.
- Limitations
- most included studies at high, serious or critical risk of bias; few controlled trials; pooled effect sizes not reported in the abstract
A randomized controlled clinical trial of a Wim Hof Method intervention in women with high depressive symptoms.
Blades R et al. Compr Psychoneuroendocrinol. 2024. PubMed 39606690 · DOI · Free full text
- Who
- healthy midlife women with high stress and high depressive symptoms (not a clinical MDD diagnosis)
- What
- daily cold showers combined with a fast-breathing/breath-hold technique (n=41) vs slow-paced breathing with warm showers (n=43), home-based with 15-min daily audio instructions
- Protocol
- coldest tap water available (not measured); control warm shower about 105 °F · cold portion 0.5 min (days 1-3), 1-3 min (days 4-6), 2-3 min thereafter min · 7/wk · 3 wk
- Measured
- depressive symptoms, anxiety symptoms, perceived stress; 3-month follow-up
- Result
- Both arms improved equivalently among completers: 24% reduction in depressive symptoms, 27% in anxiety, 20% in perceived stress, maintained at 3 months (46% mild or no depressive symptoms). No between-group difference on primary outcomes; cold-shower arm had greater reduction in rumination after daily stressors. All 6 dropouts (7%) were in the cold-shower arm.
- Limitations
- non-diagnosed population; cold component confounded with a breathing technique; water temperature not standardized; differential attrition; no no-treatment control
A randomized controlled pilot trial of low and high arousal resilience interventions for depressive symptoms.
Epel ES et al. Ann Behav Med. 2025. PubMed 41309213 · DOI
- Who
- women reporting high perceived stress (non-diagnosed)
- What
- four 3-week arms: fast breathing with cold showers; high-intensity interval training; mindfulness meditation; slow breathing with warm showers (control)
- Protocol
- 3 wk
- Measured
- depressive symptoms and perceived stress post-intervention and at 3 months; cortisol reactivity
- Result
- All four groups decreased depressive symptoms (15.93% reduction, r=.76, P<.001) and perceived stress (9.70%, r=.48, P<.001) with no group differences at post-intervention. Post hoc as-treated analysis: cold-shower arm had better maintenance of reduced depression at 3 months (r=.17, P<.01).
- Limitations
- pilot; non-diagnosed women; 3-month advantage is a post hoc analysis of adherent participants; cold exposure combined with breathing technique
Cold water swimming as an add-on treatment for depression: a feasibility study.
Hjorth P et al. Nord J Psychiatry. 2023. PubMed 37381680 · DOI
- Who
- outpatients aged 20-69 with a diagnosis of depression
- What
- supervised group cold-water swimming as add-on to usual treatment
- Protocol
- 2/wk
- Measured
- feasibility, safety, well-being score, sleep quality (PSQI)
- Result
- 13 recruited, 5 participated regularly; all passed somatic screening. In regular participants, well-being score rose from 39.2 to 54.0 and PSQI improved from 10.4 (3.7) to 8.0 (3.7). Authors conclude supervised cold-water swimming was possible and safe.
- Limitations
- open-label, uncontrolled, very small, high non-adherence (8 of 13 did not attend regularly); depression rating scale outcome not reported in abstract
Open water swimming as a treatment for major depressive disorder.
van Tulleken C et al. BMJ Case Rep. 2018. PubMed 30131418 · DOI · Free full text
- Who
- 24-year-old woman with MDD and anxiety resistant to fluoxetine and citalopram
- What
- weekly open (cold) water swimming
- Protocol
- 1/wk
- Measured
- depressive symptoms, medication use
- Result
- Immediate post-swim mood improvement and gradual sustained symptom reduction; medication reduced then stopped; medication-free at 1-year follow-up.
- Limitations
- single case report; cannot establish causation
Mindfulness training combined with cold water immersion effects on mood and perception of executive functioning in middle-aged and older adults: a pilot study.
Gentile A et al. Front Public Health. 2025. PubMed 41283028 · DOI · Free full text
- Who
- community adults, mean age 60.67 years (not selected for depression)
- What
- combined mindfulness training and cold-water immersion program
- Protocol
- 20 wk
- Measured
- depressive and anxiety symptoms, perceived executive function
- Result
- Depression score mean difference -2.59 (t=-3.10, p=0.003); anxiety improved (F=7.70, p=0.008).
- Limitations
- uncontrolled pre-post; cold exposure confounded with mindfulness; non-clinical population
Effects of cold-water immersion on health and wellbeing: A systematic review and meta-analysis.
Cain T et al. PLoS One. 2025. PubMed 39879231 · DOI · Free full text
- Who
- healthy adults (11 randomized trials)
- What
- cold shower, ice bath or plunge at 45-59 F for 30 s to 2 h
- Protocol
- 45-59 °F · 0.5-120 min
- Measured
- mood, stress, wellbeing and other outcomes
- Result
- Stress reduced 12 h post-exposure (SMD -1.00, 95% CI -1.40 to -0.61) but not at other time points; improvements in sleep quality and quality of life in narrative synthesis, but not mood.
- Limitations
- healthy adults only; few RCTs, small samples
Efficacy of the Whole-Body Cryotherapy as Add-on Therapy to Pharmacological Treatment of Depression-A Randomized Controlled Trial.
Rymaszewska J et al. Front Psychiatry. 2020. PubMed 32581890 · DOI · Free full text
- Who
- adults aged 20-73 with a diagnosed depressive episode on pharmacological treatment
- What
- WHOLE-BODY CRYOTHERAPY (cryo chamber, cold air; not water immersion): 10 sessions at -166 to -256 F vs sham at -58 F, add-on to medication
- Protocol
- -166 to -256 (cryo chamber air) °F
- Measured
- HAM-D 17, BDI-II, quality of life
- Result
- Significant group-by-time interactions for HAM-D 17 (p=0.02) and BDI-II (p=0.01); improved quality of life (p<0.05) and self-assessed mood (p=0.035).
- Limitations
- different modality from cold-water immersion; 36 of 92 did not complete; effect sizes not reported in abstract
A systematic review and meta-analysis of the effect of whole body cryotherapy on mental health problems.
Doets JJR et al. Complement Ther Med. 2021. PubMed 34655758 · DOI · Free full text
- Who
- 10 studies (6 randomized or controlled) of WBC as add-on for mental health problems
- What
- whole-body cryotherapy as add-on treatment
- Measured
- mental health problems, depressive symptoms, quality of life (Hedges' g)
- Result
- Between-group pooled effect g=0.76 (95% CI 0.17-1.36); within-group effect for depressive symptoms g=2.95 (2.44-3.45); overall within-group g=1.63 (1.05-2.21) with I2=93%.
- Limitations
- small studies; high heterogeneity; ROBINS-I risk of bias including allegiance bias; within-group effects inflate benefit
Whole Body Cryotherapy and Hyperbaric Oxygen Treatment: New Biological Treatment of Depression? A Systematic Review.
Krzystanek M et al. Pharmaceuticals (Basel). 2021. PubMed 34205729 · DOI · Free full text
- Who
- 3 clinical trials of WBC or hyperbaric oxygen in depression (from 545 records)
- What
- whole-body cryotherapy or hyperbaric oxygen as augmentation of antidepressant treatment
- Measured
- depressive symptoms
- Result
- Authors conclude WBC may be effective in augmenting antidepressants with a rapid effect, but describe the results as very preliminary.
- Limitations
- only 3 trials; narrative synthesis without pooled estimate
Whole-body cryotherapy as adjunct treatment of depressive and anxiety disorders.
Rymaszewska J et al. Arch Immunol Ther Exp (Warsz). 2008. PubMed 18250970 · DOI · Free full text
- Who
- outpatients aged 18-65 with depressive and anxiety disorders (ICD-10) on standard pharmacotherapy
- What
- whole-body cryotherapy chamber (WBC; cold air, not water immersion), 15 daily 2-3 minute sessions added to pharmacotherapy (n=26) vs pharmacotherapy alone (n=34)
- Protocol
- -166 to -256 °F · 2-3 min · 5/wk · 3 wk
- Measured
- HAM-D 17 and Hamilton Anxiety Rating Scale response (>= 50% decrease)
- Result
- After 3 weeks, HAM-D response in 34.6% vs 2.9% and HAM-A response in 46.2% vs 0% (WBC vs control).
- Limitations
- not randomized or blinded in abstract; small; mixed depressive and anxiety diagnoses
Whole-body cryotherapy - promising add-on treatment of depressive disorders.
Rymaszewska J et al. Psychiatr Pol. 2019. PubMed 31955185 · DOI · Free full text
- Who
- adults with a diagnosed depressive episode (21 completed)
- What
- whole-body cryotherapy chamber (WBC; cold air, not water immersion), 10 two-minute sessions in 2 weeks, add-on to treatment
- Protocol
- -166 to -211 °F · 2 min · 5/wk · 2 wk
- Measured
- HAM-D, BDI-II, anhedonia (SHAPS), WHOQOL-BREF, inflammatory markers
- Result
- HAM-D fell from 16.94 +/- 4.3 to 4.50 +/- 4.2 (p<0.00001) and BDI-II from 13.48 to 6.14 (p<0.03); anhedonia and quality of life improved; no change in cytokines, NO, hsCRP or ESR.
- Limitations
- observational, no control group; 9 of 30 did not complete
Influence of whole body cryotherapy on depressive symptoms - preliminary report.
Rymaszewska J et al. Acta Neuropsychiatr. 2003. PubMed 26983354 · DOI
- Who
- depressed day-hospital patients aged 37-70 continuing antidepressants
- What
- whole-body cryotherapy chamber (WBC; cold air, not water immersion), 10 sessions of 160 seconds within 2 weeks
- Protocol
- -238 °F · 2.7 min · 5/wk · 2 wk
- Measured
- HAM-D 21
- Result
- HAM-D sum scores were significantly lower after WBC in a paired t-test, with improvement on almost every item except diurnal mood variation.
- Limitations
- uncontrolled; small; medication continued; mean change not given in abstract
Protocols used in the studies
Whole-body cryotherapy trials used a chamber at -166 to -256 F (-110 to -160 C) for 2-3 minutes, once daily on weekdays for 10-15 sessions (2-3 weeks), added to antidepressant treatment. Cold-shower trials used the coldest available tap water (unmeasured) for 30 seconds rising to 2-3 minutes daily for 3 weeks, combined with a breathing technique. Cold-water swimming studies used supervised outdoor winter swimming once or twice weekly; water temperature was not reported in the abstracts. The healthy-adult meta-analysis covered water at 45-59 F (7-15 C) for 30 seconds to 2 hours.
What is still unknown
No adequately powered RCT of cold-water immersion in clinically diagnosed MDD; whether WBC findings, mostly from one research group, replicate elsewhere and last beyond a few weeks; optimal temperature, duration and frequency; whether effects exceed expectation, social contact, exercise or outdoor exposure; long-term safety in patients on psychotropic medication.
Safety
Cautions for cold therapy in this condition
- Cold shock response on entry (gasp, hyperventilation, tachycardia, blood pressure rise) can cause aspiration and arrhythmia; supervised, gradual exposure is used in clinical studies (Tipton 1989, PMID 2691172).
- Patients with depression in the feasibility study all underwent somatic evaluation before cold-water swimming (Hjorth 2023, PMID 37381680).
- Differential dropout from the cold-shower arm suggests tolerability limits (Blades 2024, PMID 39606690).
- WBC studies were supervised chamber sessions in medically screened patients continuing medication; no change in inflammatory markers and no serious adverse events were reported (PMID 31955185).
- Cold exposure should not replace evidence-based depression treatment; the 2026 meta-analysis authors state cold-water exposure is not a standalone psychiatric treatment (PMID 42819812).
- See general cold safety entry for cardiovascular, Raynaud's, cold urticaria and pregnancy cautions.
For clinicians
Suggested rationale
For cold-water immersion, evidence in diagnosed depression is weak: small uncontrolled studies describe improved well-being with supervised cold-water swimming as an add-on (Hjorth 2023), randomized trials of cold showers found no advantage over an active control (Blades 2024), and a 2026 meta-analysis concluded benefit is not established (Ngandeu Schepanski 2026). Whole-body cryotherapy in a cold-air chamber, a different procedure, improved depressive symptoms versus sham as an add-on to medication (Rymaszewska 2020), but that result does not transfer to cold plunge. Any use should be framed as an adjunct to standard care.
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