Wim Hof Method Breathing
Wim Hof Method Breathing is a breathwork practice studied in relation to stress resilience, emotional wellbeing and physical energy. Research also considers possible use across several health conditions, but these ideas are not equally well supported: some are theoretical rather than based on clinical findings.
Wim Hof Method Breathing is a breathwork practice.
Part of Breathwork
Overview
Wim Hof Method Breathing is a breathwork practice studied in relation to stress resilience, emotional wellbeing and physical energy. Research also considers possible use across several health conditions, but these ideas are not equally well supported: some are theoretical rather than based on clinical findings. Overall, the picture remains unsettled. Research has examined potential benefits, but the strength of support differs by outcome, so broad claims about what the practice can do should be treated as uncertain rather than as established effects.
Some research: 9 studies. Last checked Oct 4, 2026.
- 12
- human evidence
- 2
- eligible
- 8
- unclassified
- 7
- animal / null result
Best-evidenced uses
- Stress Resilience ImprovementMedium · Clinical
- Antidepressant EffectMedium · Clinical
- Mood ImprovementLow · Clinical
2 of 4 flagged interactions are serious or life-threatening·5 variations documented
- 9
- Studies
Evidence checked Oct 4, 2026 · newest study 2025
- C
- 7
- D
- 2
350 community reports across 4 platforms
Coverage
- Effects
- 23
- Helps with
- 6
- Side effects
- 11
- Interactions
- 11 2 high-risk
How to read the evidence
Evidence tier — overall strength of the evidence for the whole compound
- StrongWell established — backed by strong, consistent human research.
- ModerateSome genuine support, but mostly from small or lower-quality studies. Promising, not proven.
- PreliminaryEarly-stage evidence — a promising hypothesis, not an established effect yet.
- LimitedVery limited evidence — treat this as a hypothesis, not proof.
- InsufficientNot enough good evidence to draw conclusions yet.
Certainty — how sure we can be that the effect is real
- Very highVery sure — strong, consistent evidence
- HighFairly sure — consistent evidence from good studies
- MediumModerately sure — new studies could change this
- LowNot sure — little or mixed evidence
- Very lowVery unsure — almost no usable evidence
Source — where the data comes from
- Meta-analysisPooled analysis of many trials — the strongest evidence
- RCTRandomized controlled trial — a strong human study design
- ClinicalA human clinical study
- Reference knowledgeFrom general health-science or pharmacology references, not a study of this exact claim
- Animal researchStudied in animals, not humans
- Community reportsAggregated user reports — anecdotal signal, not evidence
- TheoreticalMechanism-based reasoning, not yet tested
Study grade — quality of each underlying study (A best, D weakest)
- AHigh-quality — strong, consistent human trials
- BGood — solid evidence with some limitations
- CModerate — limited, small, or mixed-quality studies
- DWeak — preliminary, indirect, or animal-only
Confidence — how strongly the sources back a finding
A 0–100 score from study quality and agreement
Most supplement evidence is graded C–D. Read it as preliminary signal, not proof.
Interacts with some medications and supplements — worth checking before combining.See interactions
These are research findings, not promises. A practice does not replace medical treatment.
What does research say?
What studies found for each claimed effect, best evidence first.
23 claims:2 some evidence10 not enough evidence2 not tested in people2 personal stories only7 no benefit found
Stress Resilience ImprovementBreathwork in general: Medium · 12 trialsSome evidence it helpsSize of effect: Not known
Some human studies found a benefit. More research could change this.
4 of 5 studies found a benefit; 1 found none. Strongest study: a randomized controlled trial. Trials that found it ran as little as 3 weeks, typically 4.
Open the Stress Resilience Improvement pageCompare with Breathwork in general →Antidepressant EffectBreathwork in general: Medium · 16 trialsSome evidence it helpsSize of effect: Not known
Some human studies found a benefit. More research could change this.
All 3 studies with a clear result found a benefit. Strongest study: a randomized controlled trial.
A pooled analysis of randomized and non-randomized human studies found depressive symptoms decreased over an 8-week training programme among 13 people in its depressive-symptom analysis. In a 2024 randomized trial of 84 participants, depressive symptoms were less likely to be reported after the intervention and at the 3-month follow-up in both conditions; the reduction at post-intervention was 20.13%.
Open the Antidepressant Effect pageCompare with Breathwork in general →Mood ImprovementBreathwork in general: Medium · 16 trialsNot enough evidence
Too few or too small studies to know if it works.
3 of 5 studies found a benefit; 2 found none. Strongest study: a randomized controlled trial.
In a 2024 randomized trial of 84 participants, daily negative affect declined soon after the intervention began, then the decline tapered and negative affect increased again toward the end; the effect sizes were small. Findings differ across trials: a 2023 randomized trial of 42 participants detected no significant time × group interactions in PANAS+.
Open the Mood Improvement pageCompare with Breathwork in general →Anxiety ReductionBreathwork in general: Medium · 23 trialsNot enough evidence
Too few or too small studies to know if it works.
1 of 2 studies found a benefit; 1 found none. Strongest study: a randomized controlled trial.
Open the Anxiety Reduction pageCompare with Breathwork in general →Physical Energy IncreaseBreathwork in general: 1 trialNot enough evidence
Too few or too small studies to know if it works.
1 of 2 studies found a benefit; 1 found none. Strongest study: a randomized controlled trial.
Open the Physical Energy Increase pageCompare with Breathwork in general →Cognitive Function ImprovementBreathwork in general: Medium · 4 trialsNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit. Strongest study: a randomized controlled trial.
Open the Cognitive Function Improvement pageCompare with Breathwork in general →Inflammation ReductionBreathwork in general: 1 trialNot enough evidence
Too few or too small studies to know if it works.
All 2 studies with a clear result found a benefit. Strongest study: a systematic review of studies.
A 2024 systematic review of randomized and non-randomized human studies reported interleukin-10 levels were 194% higher in the trained group than in the non-trained group. The review included research involving people with ankylosing spondylitis.
Open the Inflammation Reduction pageCompare with Breathwork in general →Immune System SupportBreathwork in general: 1 trialNot enough evidence
Too few or too small studies to know if it works.
All 2 studies with a clear result found a benefit. Strongest study: a systematic review of studies.
A 2024 systematic review of randomized and non-randomized human studies reported lower flu-like and self-reported symptoms, and faster recovery from fever, among participants performing the Wim Hof Method. The review included research involving people with ankylosing spondylitis.
Open the Immune System Support pageCompare with Breathwork in general →
Only reported by users, not studied: Concentration Improvement, Emotional Regulation Improvement, Present Moment Awareness, Interoception Improvement, Brain Fog Reduction, Biorhythm Regulation, and 3 more.
What to expect
No immediate benefit is reported; the benefits described were measured after multiweek programmes, with stress resilience better supported than mood. These findings concern changes assessed at the end of a programme, rather than what happens after a single session. Reports of unwanted effects span both single-session experiences and longer programmes.
Also studied in people with 6 health conditions
How strong the evidence is in each group. This is research, not a treatment recommendation.
Ankylosing SpondylitisNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit.
One randomized trial reported decreases in ESR, ASDAS-CRP and calprotectin during 8-week Wim Hof Method training. The finding comes from a review of randomized and non-randomized human studies.
Open the Ankylosing Spondylitis pageDepressionBreathwork in general: Medium · 4 trialsNot enough evidence
Too few or too small studies to know if it works.
The one study found a benefit.
An RCT involving 84 women with high depressive symptoms found lower CES-D symptom scores after the intervention and at 3-month follow-up.
Open the Depression pageCompare with Breathwork in general →Anxiety Disorder (General)Breathwork in general: Medium · 7 trialsNot tested in people
Only tested in animals, cells or theory. Results like these often do not carry over to people.
The one study found a benefit.
The practice is proposed as a possible adjunct for anxiety disorders because it may reduce anxiety and stress reactivity.
Open the Anxiety Disorder (General) pageCompare with Breathwork in general →Autoimmune Disease (General)Not tested in people
Only tested in animals, cells or theory. Results like these often do not carry over to people.
The one study found a benefit.
The method’s anti-inflammatory effects may benefit autoimmune conditions by reducing pro-inflammatory cytokines.
Open the Autoimmune Disease (General) pageChronic Fatigue SyndromeNot tested in people
Only tested in animals, cells or theory. Results like these often do not carry over to people.
The one study found a benefit.
The proposed off-label use is to support energy regulation and orthostatic tolerance through enhanced autonomic control.
Open the Chronic Fatigue Syndrome pageFibromyalgiaNot tested in people
Only tested in animals, cells or theory. Results like these often do not carry over to people.
The one study found a benefit.
The proposed rationale is to help manage central sensitization and pain perception through improved interoception and descending inhibition.
Open the Fibromyalgia page
Studied only as breathwork in general, not tested in wim hof method breathing yet
These results come from studies of breathwork as a whole. No study of wim hof method breathing has looked at them yet.
COPD (Chronic Obstructive Pulmonary Disease) (Medium · 19 trials) · Physical Endurance Increase (Medium · 14 trials) · Hypertension (High Blood Pressure) (Medium · 8 trials) · Fatigue Reduction (Medium · 8 trials) · Lung Cancer (High · 8 trials) · Physical Strength Increase (Low · 6 trials) · and 15 more
Before you try it
What studies and reports say about side effects and who it may not suit.
- Side effects
With weak evidence: Anxiety Increase, Seizure Threshold Reduction, Fainting (Syncope), Dizziness, Paresthesia (Tingling/Numbness), Muscle Cramps, and 5 more.
- May not suit you if you have
- Epilepsy, Hypertension (High Blood Pressure), Pregnancy, Recent Heart Attack (MI), Recent Stroke, Aortic Aneurysm, and 2 more
- Some trials left out people with
- Heart Disease (General) and Hypertension (High Blood Pressure)
- Serious interactions with
- Adrafinil and Citrulline
- Reported by users
- Dizziness (14 posts), Anxiety Increase (9 posts), Paresthesia (Tingling/Numbness) (7 posts), Pain (5 posts), and 10 more
- Also listed for breathwork in general (written by our reviewers)
- Pheochromocytoma · Bipolar Mania · Psychosis · Unstable Heart Disease (Unstable Angina / Decompensated Heart Failure)Precautions from the Breathwork page. They are for breathwork as a whole and may not all fit wim hof method breathing.
General wellness information, not medical advice. Ask a doctor before you start, especially if you take medicines or have a health condition.
How people do it
A gentle start, then what the studies used.
- Start with
- 12 minutes, every other day (Guided Audio Session)A gentle start based on the easiest variation, not on a study.
- Build up to
- 20 minutes, 7 times a week, high intensity (what the studies used)
- What the studies ran
- 123 minutes a week for 4 weeks
- Temperature
- 14.1 °C
The expert view shows every study, dose protocol and source.
Effects
23 listedStart here
Most likely to help, from the evidence we have
- →Stress Resilience ImprovementCertaintyMediumSourceClinicallong-term4 cited studies · 2 other sources
A pooled analysis of randomized and non-randomized human studies found a significant reduction in stress response among 13 people in its stress-response analysis, while the observed cortisol reduction was non-significant. In a 2025 randomized trial, daily Wim Hof Method Breathing produced greater momentary improvement in self-reported ability to handle stress than Meditation (MD 0.73 points [0.46, 1]).
What the sources found
5 positive · 1 neutral · 0 negativeconfidence 56/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Rating adjusted
Lowered from High to Medium after checking study quality: journal, risk of bias, trial size and design.
Who was studied
- Healthy people and patients
- Ankylosing Spondylitis
- Depression
Where the evidence comes from
- Article4
- Expert opinion1
- Community reports1
Protocol behind this outcome
2 protocolsEstimatedWhat the studies reporting this result did.
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
What worked in trials2 trials and meta-analyses
Randomized trials and meta-analyses that found this benefit: the smallest and the typical amount. Not a target and not a limit.
Smallest Typical Session 15 min 18 min How often 7×/week Per week 105 min 123 min Timing
Trials that found it ran as little as 3 weeks, typically 4
Open Stress Resilience ImprovementShow studies (6)
Systematic reviewCpositive40% confidence2024There was a significant reduction in stress response. Cortisol reduction was also observed to be non-significant.
Weak journalRCTCpositiven=40470% confidence2025WHM conditions showed greater momentary improvements in self-reported... ability to handle stress... following daily protocol compared with meditation. WHM (vs MC): Estimate 0.73 (0.14) [0.46, 1.0]
MD 0.73 [0.46, 1]Weak journalMain outcomeOpen-labelCompleters only27% dropped outRCTCpositiven=8465% confidence2024Participants in both conditions were less likely to report perceived stress at post intervention and at the 3-month follow-up... The effect size of the reduction in perceived stress for both conditions was moderate, 17.26% reduction at post-intervention and 24.83% reduction at the 3-month follow-up
MD -3.7 [-5.39, -2]Main outcomeOpen-labelCompleters onlyRCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in PSS (p = 0.364)
Weak journalOpen-labelNo control groupCompleters onlyExpert opinionpositive50% confidenceWim Hof breathing may enhance sympathetic activation and parasympathetic recovery, a key marker of stress resilience.
Expert knowledge synthesisCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 19 of 336 community reports discussing it (Reddit 14, YouTube 3, Hacker News 2).
19 mentions - →Antidepressant EffectCertaintyMediumSourceClinical3 cited studies
A pooled analysis of randomized and non-randomized human studies found depressive symptoms decreased over an 8-week training programme among 13 people in its depressive-symptom analysis. In a 2024 randomized trial of 84 participants, depressive symptoms were less likely to be reported after the intervention and at the 3-month follow-up in both conditions; the reduction at post-intervention was 20.13%.
What the sources found
3 positive · 0 neutral · 0 negativeconfidence 45/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people and patients
- Ankylosing Spondylitis
- Depression
Where the evidence comes from
- Article3
Protocol behind this outcome
2 protocolsEstimatedWhat the studies reporting this result did.
18 min · 7×/week
- Course
- 6 weeks
- Per week
- 123 min
- Intensity
- High
- Format
- Individual
- Supervision
- Self-guided
A repeated course
Open Antidepressant EffectShow studies (3)
Systematic reviewCpositive40% confidence2024Depressive symptoms decreased over an 8-week training programme.
Weak journalRCTCpositiven=8465% confidence2024Compared to baseline scores, participants in both conditions were less likely to report depressive symptoms post-intervention and at the 3-month follow-up... The effect size of the reduction in depressive symptoms for those in both conditions was moderate (20.13% reduction at post-intervention and 3
MD -4.25 [-7.2, -1.3]Main outcomeOpen-labelCompleters onlyCohort studyDpositiven=1330% confidence2022The results of the Mann–Whitney test showed no differences between the groups in all assessed variables at the beginning of the expedition (before WMH training). However, there were significant differences at the end of the expedition between the WMH intervention group and the control group in the l
MD -5.35Weak journalMain outcomeOpen-labelNo control groupCompleters onlyBorderline p-value
Low probability(17)
- →Mood ImprovementCertaintyLowSourceClinical5 cited studies · 1 other source
In a 2024 randomized trial of 84 participants, daily negative affect declined soon after the intervention began, then the decline tapered and negative affect increased again toward the end; the effect sizes were small. Findings differ across trials: a 2023 randomized trial of 42 participants detected no significant time × group interactions in PANAS+ (p = 0.427).
What the sources found
4 positive · 2 neutral · 0 negativeconfidence 50/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Rating adjusted
Lowered from Medium to Low after checking study quality: journal, risk of bias, trial size and design.
Who was studied
- Healthy people and patients
- Depression
Where the evidence comes from
- Article5
- Community reports1
Protocol behind this outcome
2 protocolsEstimatedWhat the studies reporting this result did.
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
What worked in trials2 trials and meta-analyses
Randomized trials and meta-analyses that found this benefit: the smallest and the typical amount. Not a target and not a limit.
Smallest Typical Session 15 min 18 min How often 7×/week Per week 105 min 123 min Timing
Trials that found it ran as little as 3 weeks, typically 4
Open Mood ImprovementShow studies (6)
RCTCpositiven=40455% confidence2025intriguingly, post-intervention psychological safety
Weak journalOpen-labelCompleters only27% dropped outRCTCpositiven=8450% confidence2024Both groups showed a decline in daily negative affect soon after the start of the intervention, which then tapered off and increased again towards the end of the intervention. The effect sizes were small.
Open-labelCompleters onlyRCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in PANAS+ (p = 0.427)
Weak journalOpen-labelNo control groupCompleters onlyCross SectionalCpositiven=13260% confidence2025Wellbeing scores were significantly greater in the current sample (M=55.07, SD=7.31) than in the pre-pandemic sample (M=49.4, SD=9.08) (t(131)=8.91, p<.001), d=0.78; and than during-COVID sample (M=45.4) (t(131)=15.20, p<.001), d=1.32.
SMD 0.78Moderate effectMain outcomeOpen-labelNo control groupPilot studyDneutraln=1025% confidence2023MHI-5 showed a trend (p = 0.091) for improvement between T1 and T2. Figure 1C shows that participants with a low MHI-5 score at T1 improved most. The number of participants with severe mental health problems (≤60 points) decreased from four to one, the number of people with mental health problems (>
Low-quality journalOpen-labelNo control groupCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 63 of 336 community reports discussing it (Reddit 56, YouTube 5, Hacker News 2).
63 mentions - →Anxiety ReductionCertaintyLowSourceClinicallong-term2 cited studies · 1 other source
In a 2024 randomized trial of 84 participants studied in relation to depression, anxiety symptoms were less likely to be reported after the intervention and at the 3-month follow-up in both conditions. The reported effect was trivial (MD -1.471 points [-2.776, -0.166]).
What the sources found
2 positive · 1 neutral · 0 negativeconfidence 60/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people and patients
- Depression
Where the evidence comes from
- Article2
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
15 min · 7×/week
- Course
- 3 weeks
- Per week
- 105 min
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
Open Anxiety ReductionShow studies (3)
RCTCneutraln=40465% confidence2025For stress, the Meditation condition showed a significantly greater momentary decrease than the WHM condition, while no difference emerged between WHM-remote and Meditation. WHM (vs MC): Estimate 0.37 (0.11) [0.16, 0.58]
MD 0.37 [0.16, 0.58]Weak journalMain outcomeOpen-labelCompleters only27% dropped outRCTCpositiven=8465% confidence2024Participants in both conditions were less likely to report symptoms of anxiety symptoms at post intervention and at the 3-month follow-up... The effect size of the reduction in anxiety for both conditions was moderate (20.93% reduction post-intervention and 39.30% reduction at 3-months)
MD -1.47 [-2.78, -0.17]Trivial effectMain outcomeOpen-labelCompleters onlyBorderline p-valueCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 86 of 346 community reports discussing it (Reddit 82, Bluesky 2, YouTube 2).
86 mentions - →Physical Energy IncreaseCertaintyLowSourceClinicallong-term2 cited studies · 1 other source
In a 2025 randomized trial of 404 healthy participants, a daily Wim Hof Method protocol produced greater momentary self-reported energy improvement than meditation: MD 1.44 points [1.15, 1.74]. Results differ across trials: a 2023 randomized trial of 42 participants detected no significant time × group interactions in SVSt (p = 0.760).
What the sources found
2 positive · 1 neutral · 0 negativeconfidence 60/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article2
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
20 min · 7×/week
- Course
- 4 weeks
- Per week
- 140 min
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
Open Physical Energy IncreaseShow studies (3)
RCTCpositiven=40470% confidence2025WHM conditions showed greater momentary improvements in self-reported energy... following daily protocol compared with meditation. WHM (vs MC): Estimate 1.44 (0.15) [1.15, 1.74]
MD 1.44 [1.15, 1.74]Weak journalMain outcomeOpen-labelCompleters only27% dropped outRCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in SVSt (p = 0.760)
Weak journalOpen-labelNo control groupCompleters onlyCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 28 of 315 Reddit reports discussing it.
28 mentions - →Cognitive Function ImprovementCertaintyLowSourceClinicallong-term1 cited study · 1 other source
In a 2025 randomized trial of 404 healthy participants, a daily Wim Hof Method protocol led to greater momentary self-reported mental clarity improvement than meditation: MD 1 points [0.7, 1.3].
What the sources found
2 positive · 0 neutral · 0 negativeconfidence 60/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
20 min · 7×/week
- Course
- 4 weeks
- Per week
- 140 min
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
Open Cognitive Function ImprovementShow studies (2)
RCTCpositiven=40470% confidence2025WHM conditions showed greater momentary improvements in self-reported... mental clarity... following daily protocol compared with meditation. WHM (vs MC): Estimate 1.0 (0.15) [0.70, 1.3]
MD 1 [0.7, 1.3]Weak journalMain outcomeOpen-labelCompleters only27% dropped outCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 13 of 315 Reddit reports discussing it.
13 mentions - →Inflammation ReductionCertaintyLowSourceClinical1 cited study · 2 other sources
A 2024 systematic review of randomized and non-randomized human studies reported interleukin-10 levels were 194% higher in the trained group than in the non-trained group. The review included research involving people with ankylosing spondylitis.
What the sources found
3 positive · 0 neutral · 0 negativeconfidence 50/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people and patients
- Ankylosing Spondylitis
Where the evidence comes from
- Article1
- Expert opinion1
- Community reports1
Open Inflammation ReductionShow studies (3)
Systematic reviewCpositive60% confidence2024interleukin-10 levels were 194% higher compared to non-trained group
194%Large effectWeak journalExpert opinionpositive50% confidenceThe Wim Hof breathing method may reduce inflammatory markers and modulate the immune response.
Expert knowledge synthesisCommunity reportsstrong effectpositive40% confidenceThis effect was mentioned in 5 of 315 Reddit reports discussing it.
5 mentions - →Immune System SupportCertaintyLowSourceClinical1 cited study · 2 other sources
A 2024 systematic review of randomized and non-randomized human studies reported lower flu-like and self-reported symptoms, and faster recovery from fever, among participants performing the Wim Hof Method. The review included research involving people with ankylosing spondylitis.
What the sources found
3 positive · 0 neutral · 0 negativeconfidence 50/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people and patients
- Ankylosing Spondylitis
Where the evidence comes from
- Article1
- Expert opinion1
- Community reports1
Open Immune System SupportShow studies (3)
Systematic reviewCpositive50% confidence2024Kox et al. reported lower flu-like and self-reported symptoms and faster recovery from fever in participants performing WHM.
Weak journalExpert opinionpositive50% confidenceThe practice acutely increases epinephrine and anti-inflammatory cytokines, enhancing the body's ability to suppress inflammation and potentially improving immune function.
Expert knowledge synthesisCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 7 of 315 Reddit reports discussing it.
7 mentions - →Respiratory Rate OptimizationCertaintyLowSourceClinical1 cited study · 1 other source
A 2025 randomized trial of 404 healthy participants found that Wim Hof Method practices appeared to decrease nightly respiratory rate beyond meditation. The finding does not give the size of the decrease.
What the sources found
2 positive · 0 neutral · 0 negativeconfidence 40/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
20 min · 7×/week
- Course
- 4 weeks
- Per week
- 140 min
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
Open Respiratory Rate OptimizationShow studies (2)
RCTCpositiven=40455% confidence2025WHM practices (over and above Meditation) appeared to decrease nightly respiratory rate
Weak journalOpen-labelCompleters only27% dropped outCommunity reportsmoderate effectpositive25% confidenceThis effect was mentioned in 2 of 315 Reddit reports discussing it.
2 mentions - →Sleep Quality ImprovementCertaintyLowSourceClinical1 cited study · 1 other source
A 2023 pilot study of 10 participants found improved sleep quality (p = 0.018). The finding comes from people with a clinical condition.
What the sources found
2 positive · 0 neutral · 0 negativeconfidence 40/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- People with a condition
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
30 min · 1×/week
- Course
- 4 weeks
- Per week
- 30 min
- Format
- Group
- Supervision
- Instructor-led
A repeated course
Open Sleep Quality ImprovementShow studies (2)
Pilot studyDpositiven=1030% confidence2023Sleep quality showed a significant improvement (p = 0.018) (Figure 1E).
Low-quality journalOpen-labelNo control groupCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 26 of 332 community reports discussing it (Reddit 24, YouTube 2).
26 mentions - →Respiratory Health SupportCertaintyLowSourceClinical1 cited study · 1 other source
A 2023 pilot study of 10 participants found that the hyperventilation sumscore decreased after the intervention. The finding was measured in people with a clinical condition.
What the sources found
2 positive · 0 neutral · 0 negativeconfidence 30/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- People with a condition
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
30 min · 1×/week
- Course
- 4 weeks
- Per week
- 30 min
- Format
- Group
- Supervision
- Instructor-led
A repeated course
Open Respiratory Health SupportShow studies (2)
Pilot studyDpositiven=1030% confidence2023Nonetheless, the hyperventilation sumscore was significantly decreased following the intervention (Figure 1B).
Low-quality journalOpen-labelNo control groupCommunity reportsmoderate effectpositive30% confidenceThis effect was mentioned in 3 of 315 Reddit reports discussing it.
3 mentions - →Lung Capacity ImprovementCertaintyLowSourceClinical1 cited study
A 2023 pilot study of 10 participants found that FVC improved from T1 to T2; the effect size was large for all five respiratory parameters. The finding comes from a small pilot study in people with a clinical condition.
What the sources found
1 positive · 0 neutral · 0 negativeconfidence 30/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- People with a condition
Where the evidence comes from
- Article1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
30 min · 1×/week
- Course
- 4 weeks
- Per week
- 30 min
- Format
- Group
- Supervision
- Instructor-led
A repeated course
Open Lung Capacity ImprovementShow studies (1)
Pilot studyDpositiven=1030% confidence2023A statistically significant improvement was found in the respiratory parameter FVC from T1 to T2 (Figure 1A). The effect size was large for all five respiratory parameters.
Low-quality journalOpen-labelNo control group - →Vagal Tone ImprovementCertaintyLowSourceAnecdotallong-termnot used for recommendations2 other sources
Expert knowledge proposes that extended exhalation and apnea phases stimulate vagal reactivation, followed by a parasympathetic rebound after breath-holding. This effect was mentioned in 6 of 315 Reddit reports; these are community reports, not clinical findings.
What the sources found
2 positive · 0 neutral · 0 negativeconfidence 48/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion1
- Community reports1
Why it isn't used for recommendations
No supporting study on file
Open Vagal Tone ImprovementShow studies (2)
Expert opinionpositive50% confidenceExtended exhalation and apnea phases stimulate vagal reactivation, enhancing parasympathetic rebound post-breath-hold.
Expert knowledge synthesisCommunity reportsmoderate effectpositive45% confidenceThis effect was mentioned in 6 of 315 Reddit reports discussing it.
6 mentions - →Breath Hold Time ImprovementCertaintyLowSourceAnecdotallong-termnot used for recommendations2 other sources
Expert knowledge proposes that regular practice increases tolerance to hypercapnia and hypoxia, extending voluntary apnea duration. This effect was mentioned in 4 of 315 Reddit reports; these are community reports, not clinical findings.
What the sources found
2 positive · 0 neutral · 0 negativeconfidence 43/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion1
- Community reports1
Why it isn't used for recommendations
No supporting study on file
Open Breath Hold Time ImprovementShow studies (2)
Expert opinionpositive50% confidenceRegular practice increases tolerance to hypercapnia and hypoxia, extending voluntary apnea duration.
Expert knowledge synthesisCommunity reportsmoderate effectpositive35% confidenceThis effect was mentioned in 4 of 315 Reddit reports discussing it.
4 mentions - →Nitric Oxide Production IncreaseCertaintyLowSourceTheoreticalnot used for recommendations1 other source
Expert knowledge proposes that rapid breathing increases nitric oxide release from the sinuses and endothelium, which may improve vasodilation and oxygen delivery.
What the sources found
1 positive · 0 neutral · 0 negativeconfidence 50/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion1
Why it isn't used for recommendations
No supporting study on file
Open Nitric Oxide Production IncreaseShow studies (1)
Expert opinionpositive50% confidenceRapid breathing increases nitric oxide release from sinuses and endothelium, improving vasodilation and oxygen delivery.
Expert knowledge synthesis - →Mitochondrial Function SupportCertaintyLowSourceTheoreticallong-termnot used for recommendations1 other source
Expert knowledge proposes that cyclic hypoxia-reoxygenation may stimulate mitochondrial biogenesis through HIF-1α and PGC-1α pathways.
What the sources found
1 positive · 0 neutral · 0 negativeconfidence 40/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion1
Why it isn't used for recommendations
No supporting study on file
Open Mitochondrial Function SupportShow studies (1)
Expert opinionpositive40% confidenceCyclic hypoxia-reoxygenation may stimulate mitochondrial biogenesis via HIF-1α and PGC-1α pathways.
Expert knowledge synthesis - →Cardiovascular Health SupportCertaintyLowSourceTheoreticalnot used for recommendations1 cited study · 1 other source
A randomized trial of 42 healthy participants found no significant time × group interactions in PWV (p = 0.983), so the studies did not support a cardiovascular benefit.
What the sources found
1 positive · 1 neutral · 0 negativeconfidence 45/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
- Community reports1
Why it isn't used for recommendations
Studied, with no positive result
Open Cardiovascular Health SupportShow studies (2)
RCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in PWV (p = 0.983)
Weak journalMain outcomeOpen-labelNo control groupCompleters onlyCommunity reportsmoderate effectpositive30% confidenceThis effect was mentioned in 3 of 315 Reddit reports discussing it.
3 mentions - →Analgesic EffectCertaintyLowSourceTheoreticalnot used for recommendations2 cited studies · 1 other source
The studies did not support an analgesic effect: a 2023 randomized trial of 42 participants detected no significant time × group interaction in perceived pain (p = 0.231).
What the sources found
1 positive · 2 neutral · 0 negativeconfidence 35/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people and patients
Where the evidence comes from
- Article2
- Community reports1
Why it isn't used for recommendations
Studied, with no positive result
Open Analgesic EffectShow studies (3)
RCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in perceived pain (p = 0.231)
Weak journalOpen-labelNo control groupCompleters onlyPilot studyDneutraln=1020% confidence2023No significant changes were found in pain intensity or pain interference.
Low-quality journalOpen-labelNo control groupCommunity reportsmoderate effectpositive25% confidenceThis effect was mentioned in 2 of 315 Reddit reports discussing it.
2 mentions - →Muscle RelaxationCertaintyLowSourceTheoreticalnot used for recommendations1 cited study · 1 other source
The studies did not support muscle relaxation: in a 2023 pilot of 10 people with a clinical condition, spasticity and its interference with daily activities did not change significantly. Discomfort related to spasticity showed a trend toward less discomfort or hindrance (p = 0.088).
What the sources found
1 positive · 1 neutral · 0 negativeconfidence 35/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- People with a condition
Where the evidence comes from
- Article1
- Community reports1
Why it isn't used for recommendations
Studied, with no positive result
Open Muscle RelaxationShow studies (2)
Pilot studyDneutraln=1020% confidence2023The degree of spasticity as well as the hindrance of spasticity during daily life activities did not change significantly between T1 and T2. The discomfort due to spasticity showed a trend (p = 0.088) towards less discomfort or hindrance (Figure 1F).
Low-quality journalOpen-labelNo control groupCommunity reportsmoderate effectpositive50% confidenceThis effect was mentioned in 7 of 315 Reddit reports discussing it.
7 mentions
Very low probability(4)
- →Improve Heart Rate Variability (HRV)CertaintyVery lowSourceClinicalnot used for recommendations1 cited study
A randomized trial of 42 healthy participants found no significant time × group interactions in RMSSD (p = 0.820), so the studies did not support an improvement in heart rate variability.
What the sources found
0 positive · 1 neutral · 0 negativeconfidence 60/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
Why it isn't used for recommendations
Studied, with no positive result
Open Improve Heart Rate Variability (HRV)Show studies (1)
RCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in RMSSD (p = 0.820)
Weak journalMain outcomeOpen-labelNo control groupCompleters only - →Resting Heart Rate ImprovementCertaintyVery lowSourceClinicalnot used for recommendations1 cited study
A randomized trial of 42 healthy participants found no significant time × group interactions in HR (p = 0.709), so the studies did not support an improvement in resting heart rate.
What the sources found
0 positive · 1 neutral · 0 negativeconfidence 60/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
Why it isn't used for recommendations
Studied, with no positive result
Open Resting Heart Rate ImprovementShow studies (1)
RCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in HR (p = 0.709)
Weak journalMain outcomeOpen-labelNo control groupCompleters only - →Blood Pressure SupportCertaintyVery lowSourceClinicalnot used for recommendations2 cited studies
A randomized trial of 42 participants found no significant time × group interactions in systolic BP (p = 0.839), so the studies did not support a blood-pressure benefit.
What the sources found
0 positive · 2 neutral · 0 negativeconfidence 40/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people and patients
Where the evidence comes from
- Article2
Why it isn't used for recommendations
Studied, with no positive result
Open Blood Pressure SupportShow studies (2)
RCTCneutraln=4260% confidence2023No significant time × group interactions could be detected in systolic BP (p = 0.839)
Weak journalMain outcomeOpen-labelNo control groupCompleters onlyPilot studyDneutraln=1020% confidence2023In contrast, blood pressure did not significantly change over time.
Low-quality journalOpen-labelNo control group - →Trauma Symptom ReductionCertaintyVery lowSourceClinicalnot used for recommendations1 cited study
The studies did not support trauma symptom reduction. In a 2022 cohort of 13 healthy people, cortisol levels and TSC-40 (stress) scores were higher in the control group at the end of the expedition, but these differences were not significant.
What the sources found
0 positive · 1 neutral · 0 negativeconfidence 20/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
Why it isn't used for recommendations
Studied, with no positive result
Open Trauma Symptom ReductionShow studies (1)
Cohort studyDneutraln=1320% confidence2022At the end of the expedition, cortisol levels and TSC-40 (stress) scores were higher in the control group; however, these differences were not significant.
MD -11.58Weak journalOpen-labelNo control groupCompleters only
9 more mentioned only by users
What to expect
No immediate benefit is reported; the benefits described were measured after multiweek programmes, with stress resilience better supported than mood. These findings concern changes assessed at the end of a programme, rather than what happens after a single session. Reports of unwanted effects span both single-session experiences and longer programmes.
Conditions it's used for
Complaints and diagnoses people take it for6 listedThe best we have, but the evidence is still weak
- →Ankylosing SpondylitisCertaintyLowSourceClinical1 cited study
One randomized trial reported decreases in ESR, ASDAS-CRP and calprotectin during 8-week Wim Hof Method training. The finding comes from a review of randomized and non-randomized human studies.
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people and patients
- Ankylosing Spondylitis
Open Ankylosing SpondylitisShow studies (1)
Systematic reviewC55% confidence2024One RCT (Buijze et al., 2019) showed significant decreases in inflammatory markers (ESR, ASDAS-CRP, calprotectin) during 8-week WHM training.
Weak journal - →DepressionCertaintyLowSourceClinical1 cited study
An RCT involving 84 women with high depressive symptoms found lower CES-D symptom scores after the intervention and at 3-month follow-up.
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- People with a condition
- Depression
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
15 min · 7×/week
- Course
- 3 weeks
- Per week
- 105 min
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
Open DepressionShow studies (1)
RCTCn=8465% confidence2024RCT showing significant reductions in depressive symptoms (CES-D) post-intervention and at 3-month follow-up in women with high depressive symptoms
Open-labelCompleters only - →Anxiety Disorder (General)CertaintyLowSourceTheoreticalnot used for recommendations1 other source
The practice is proposed as a possible adjunct for anxiety disorders because it may reduce anxiety and stress reactivity.
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion
Why it isn't used for recommendations
No supporting study on file
Open Anxiety Disorder (General)Show studies (1)
Expert opinion50% confidenceThe practice reduces anxiety and stress reactivity, making it a potential adjunctive therapy for anxiety disorders.
- →Autoimmune Disease (General)CertaintyLowSourceTheoreticalnot used for recommendations1 other source
The method’s anti-inflammatory effects may benefit autoimmune conditions by reducing pro-inflammatory cytokines.
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion
Why it isn't used for recommendations
No supporting study on file
Open Autoimmune Disease (General)Show studies (1)
Expert opinion50% confidenceThe method's anti-inflammatory effects may benefit autoimmune conditions by reducing pro-inflammatory cytokines.
- →Chronic Fatigue SyndromeCertaintyLowSourceTheoreticalnot used for recommendations1 other source
The proposed off-label use is to support energy regulation and orthostatic tolerance through enhanced autonomic control.
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion
Why it isn't used for recommendations
No supporting study on file
Open Chronic Fatigue SyndromeShow studies (1)
Expert opinion50% confidenceUsed off-label to improve energy regulation and orthostatic tolerance via enhanced autonomic control.
- →FibromyalgiaCertaintyLowSourceTheoreticalnot used for recommendations1 other source
The proposed rationale is to help manage central sensitization and pain perception through improved interoception and descending inhibition.
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Expert opinion
Why it isn't used for recommendations
No supporting study on file
Open FibromyalgiaShow studies (1)
Expert opinion50% confidenceHelps manage central sensitization and pain perception through improved interoception and descending inhibition.
Studied only as breathwork in general, not tested in wim hof method breathing yet
These results come from studies of breathwork as a whole. No study of wim hof method breathing has looked at them yet.
COPD (Chronic Obstructive Pulmonary Disease) (Medium · 19 trials) · Physical Endurance Increase (Medium · 14 trials) · Hypertension (High Blood Pressure) (Medium · 8 trials) · Fatigue Reduction (Medium · 8 trials) · Lung Cancer (High · 8 trials) · Physical Strength Increase (Low · 6 trials) · and 15 more
Side effects
11 listedHighest probability
- →Anxiety IncreaseCertaintyLowSourceClinical1 cited study · 1 other source
The findings did not support increased anxiety: a randomized trial of 404 healthy participants found a greater decrease in anxiety in the meditation condition than in WHM-remote after the 29-day intervention.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 55/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
20 min · 7×/week
- Course
- 4 weeks
- Per week
- 140 min
- Intensity
- High
- Format
- Self-guided
- Supervision
- Self-guided
A repeated course
Open Anxiety IncreaseShow studies (2)
RCTCnegativen=40460% confidence2025results revealed a greater decrease in the anxiety subscale of the DASS-21 in the meditation condition compared to WHM-remote at the completion of the 29-day intervention, W=4717.00, p=0.044, 95% CI [0.00, 0.13], r=0.003
Weak journalOpen-labelCompleters only27% dropped outCommunity reportsnegative50% confidenceThis effect was mentioned in 9 of 315 Reddit reports discussing it.
- →DizzinessCertaintyLowSourceClinical1 cited study · 1 other source
A randomized trial in 2021 recorded dizziness among 15 healthy participants.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 48/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolMeasuredWhat the studies reporting this result did.
12 min
- Intensity
- High
- Format
- Individual
- Supervision
- Instructor-led
Single sessions · 0 repeated-course and 1 single-session protocols
Open DizzinessShow studies (2)
RCTCnegativen=1545% confidence2021Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study.
Dizziness
Weak journalOpen-labelCompleters onlyCommunity reportsnegative50% confidenceThis effect was mentioned in 14 of 315 Reddit reports discussing it.
- →Paresthesia (Tingling/Numbness)CertaintyLowSourceClinical1 cited study · 1 other source
A randomized trial in 2021 recorded tingling among 15 healthy participants.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 48/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolMeasuredWhat the studies reporting this result did.
12 min
- Intensity
- High
- Format
- Individual
- Supervision
- Instructor-led
Single sessions · 0 repeated-course and 1 single-session protocols
Open Paresthesia (Tingling/Numbness)Show studies (2)
RCTCnegativen=1545% confidence2021Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study.
Tingling
Weak journalOpen-labelCompleters onlyCommunity reportsnegative50% confidenceThis effect was mentioned in 7 of 315 Reddit reports discussing it.
- →Muscle StrainCertaintyLowSourceClinical1 cited study
A randomized trial in 2021 recorded lower-limb muscular injury among 15 healthy participants.
What the sources found
0 not observed · 0 unclear · 1 reportedconfidence 45/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
Protocol behind this outcome
1 protocolMeasuredWhat the studies reporting this result did.
12 min
- Intensity
- High
- Format
- Individual
- Supervision
- Instructor-led
Single sessions · 0 repeated-course and 1 single-session protocols
Open Muscle StrainShow studies (1)
RCTCnegativen=15Had it: 1 of 1645% confidence2021Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study.
Muscular injury (lower limb)
Weak journalOpen-labelCompleters only - →WeaknessCertaintyLowSourceClinical1 cited study · 1 other source
A randomized trial in 2021 recorded a sensation of heaviness among 15 healthy participants.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 35/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- Healthy people
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolMeasuredWhat the studies reporting this result did.
12 min
- Intensity
- High
- Format
- Individual
- Supervision
- Instructor-led
Single sessions · 0 repeated-course and 1 single-session protocols
Open WeaknessShow studies (2)
RCTCnegativen=1545% confidence2021Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study.
Heaviness
Weak journalOpen-labelCompleters onlyCommunity reportsnegative25% confidenceThis effect was mentioned in 2 of 315 Reddit reports discussing it.
- →Physical FatigueCertaintyLowSourceClinical1 cited study · 1 other source
In a 2023 pilot involving 10 people with a clinical condition, FSS scores increased unfavorably and significantly. The number in the severe fatigue category rose from 2 before the intervention to 4 afterward.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 30/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Who was studied
- People with a condition
Where the evidence comes from
- Article1
- Community reports1
Protocol behind this outcome
1 protocolEstimatedWhat the studies reporting this result did.
30 min · 1×/week
- Course
- 4 weeks
- Per week
- 30 min
- Format
- Group
- Supervision
- Instructor-led
A repeated course
Open Physical FatigueShow studies (2)
Pilot studyDnegativen=1030% confidence2023The FSS showed an unfavorable and significant increase between measurements (Figure 1D). This was underscored by a shift of participants from the no fatigue (pre: N = 5 to post: N = 3) or fatigue (pre: N = 3 to post: N = 3) categories to the severe fatigue category (pre: N = 2 to post: N = 4).
Low-quality journalOpen-labelNo control groupCommunity reportsnegative30% confidenceThis effect was mentioned in 3 of 315 Reddit reports discussing it.
- →Seizure Threshold ReductionCertaintyLowSourceReference knowledge1 other source
Hyperventilation can provoke seizures in people with seizure susceptibility, making this a particular concern for people with epilepsy.
What the sources found
0 not observed · 0 unclear · 1 reportedconfidence 75/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Reference knowledge1
Open Seizure Threshold ReductionShow studies (1)
Reference knowledgenegative75% confidenceHyperventilation can provoke seizures in people with seizure susceptibility; this is a particular concern for people with epilepsy.
Low probability(4)
- →Fainting (Syncope)CertaintyLowSourceReference knowledge2 other sources
Repeated hyperventilation followed by breath retention can cause temporary loss of consciousness, particularly when practiced standing or near water.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 60/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Community reports1
- Reference knowledge1
Open Fainting (Syncope)Show studies (2)
Reference knowledgenegative80% confidenceRepeated hyperventilation followed by breath retention can cause transient loss of consciousness, particularly if performed standing or near water.
Community reportsnegative40% confidenceThis effect was mentioned in 5 of 315 Reddit reports discussing it.
- →Muscle CrampsCertaintyLowSourceReference knowledge1 other source
Alkalosis-related decreases in calcium and potassium can increase membrane excitability and trigger involuntary muscle contractions.
What the sources found
0 not observed · 0 unclear · 1 reportedconfidence 60/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Reference knowledge1
Open Muscle CrampsShow studies (1)
Reference knowledgenegative60% confidenceAlkalosis-induced hypocalcemia and hypokalemia increase membrane excitability, triggering involuntary contractions.
- →HyperventilationCertaintyLowSourceReference knowledge2 other sources
Excessive CO2 expulsion can cause temporary respiratory alkalosis, which lowers ionized calcium and can lead to neuromuscular irritability.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 53/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Community reports1
- Reference knowledge1
Open HyperventilationShow studies (2)
Reference knowledgenegative80% confidenceCore mechanism involves transient respiratory alkalosis from excessive CO2 expulsion, leading to ionized calcium drop and neuromuscular irritability.
Community reportsnegative25% confidenceThis effect was mentioned in 2 of 315 Reddit reports discussing it.
- →Heart Rhythm DisturbanceCertaintyLowSourceReference knowledge2 other sources
Autonomic activation and electrolyte shifts may lead to palpitations or arrhythmias. People have also reported heart rhythm disturbances in connection with this practice.
What the sources found
0 not observed · 0 unclear · 2 reportedconfidence 40/100
How big is the effect
No study gave a number we could compare, so the size is not known.
Where the evidence comes from
- Community reports1
- Reference knowledge1
Open Heart Rhythm DisturbanceShow studies (2)
Reference knowledgenegative50% confidencePalpitations or arrhythmias from autonomic activation and electrolyte shifts.
Community reportsnegative30% confidenceThis effect was mentioned in 3 of 315 Reddit reports discussing it.
Don't do it if
When to skip it or get medical advice first8 listedHighest probability
- →EpilepsyCertaintyLowSourceReference knowledgeTheoretical
Hyperventilation can trigger seizures in people susceptible to them.
In the trials
1 trial of this practice also left out people with this condition. That does not show harm.
PubMed links (1)
Where the evidence comes from
- Reference knowledge
Confidence
confidence 85/100
Open EpilepsyRationale
Hyperventilation is a known trigger for seizures in susceptible individuals.
- →Hypertension (High Blood Pressure)CertaintyLowSourceReference knowledgeTheoretical
The practice can acutely raise blood pressure; uncontrolled high blood pressure increases cardiovascular event risk.
In the trials
2 trials of this practice also left out people with this condition. That does not show harm.
PubMed links (2)
Where the evidence comes from
- Reference knowledge
Confidence
confidence 80/100
Open Hypertension (High Blood Pressure)Rationale
The practice can acutely increase blood pressure; uncontrolled hypertension increases risk of cardiovascular events.
- →PregnancyCertaintyLowSourceReference knowledgeTheoretical
Fainting and low oxygen may compromise fetal oxygenation, and safety during pregnancy has not been established.
In the trials
1 trial of this practice also left out people with this condition. That does not show harm.
PubMed links (1)
Where the evidence comes from
- Reference knowledge
Confidence
confidence 80/100
Open PregnancyRationale
Risk of syncope and hypoxia may compromise fetal oxygenation; safety not established.
- →Recent Heart Attack (MI)CertaintyLowSourceReference knowledgeTheoretical
Increased cardiac demand and blood pressure may place stress on the healing heart muscle after a recent heart attack.
Where the evidence comes from
- Reference knowledge
Confidence
confidence 80/100
Open Recent Heart Attack (MI)Rationale
Increased cardiac demand and blood pressure may stress the healing myocardium.
- →Recent StrokeCertaintyLowSourceReference knowledgeTheoretical
Changes in cerebral blood flow and the possibility of low or high blood pressure may pose risks after a stroke.
Where the evidence comes from
- Reference knowledge
Confidence
confidence 80/100
Open Recent StrokeRationale
Altered cerebral blood flow and risk of hypotension/hypertension may be dangerous post-stroke.
- →Aortic AneurysmCertaintyLowSourceReference knowledgeTheoretical
Breath holds can increase pressure in the chest and raise blood pressure, stressing the aortic wall and risking rupture.
Where the evidence comes from
- Reference knowledge
Confidence
confidence 75/100
Open Aortic AneurysmRationale
Increased intrathoracic pressure during breath holds can raise blood pressure and stress the aortic wall, risking rupture.
- →Heart ArrhythmiaCertaintyLowSourceReference knowledgeTheoretical
The sympathetic surge and electrolyte shifts during breath cycling may trigger atrial or ventricular arrhythmias in susceptible people.
Where the evidence comes from
- Reference knowledge
Confidence
confidence 75/100
Open Heart ArrhythmiaRationale
Sympathetic surge and electrolyte shifts during breath cycling may trigger atrial or ventricular arrhythmias in susceptible individuals.
Low probability(1)
- →GlaucomaCertaintyLowSourceReference knowledgeTheoretical
Forced exhalation and breath holding can increase pressure in the chest and raise pressure inside the eye, which may risk optic nerve damage.
In the trials
1 trial of this practice also left out people with this condition. That does not show harm.
PubMed links (1)
Where the evidence comes from
- Reference knowledge
Confidence
confidence 65/100
Open GlaucomaRationale
Increased intrathoracic pressure during forced exhalation and breath holding elevates intraocular pressure, risking optic nerve damage.
Who the trials left out
Some trials of this practice did not take people with these conditions, so the studies say less about them. This is not a warning and does not show harm. Ask a clinician first.13 listed- Heart Disease (General)left out by 2 trials
PubMed links (2)
PubMed links (2)
Left out by one trial each (11)
- Drug Addictionleft out by 1 trial
PubMed links (1)
- Asthmaleft out by 1 trial
PubMed links (1)
- Bipolar Disorderleft out by 1 trial
PubMed links (1)
- Diabetes (General)left out by 1 trial
PubMed links (1)
PubMed links (1)
PubMed links (1)
- Hearing Lossleft out by 1 trial
PubMed links (1)
- Panic Disorderleft out by 1 trial
PubMed links (1)
PubMed links (1)
- Psychosisleft out by 1 trial
PubMed links (1)
- Raynaud's Phenomenonleft out by 1 trial
PubMed links (1)
Also listed for breathwork in general (written by our reviewers)
Precautions from the Breathwork page. They are for breathwork as a whole and may not all fit wim hof method breathing.
Pheochromocytoma · Bipolar Mania · Psychosis · Unstable Heart Disease (Unstable Angina / Decompensated Heart Failure)
Interactions
Dangerous combinations
Highest severity first
- →SupplementsAdrafinilTheoreticalSerious
Adrafinil can add to central nervous system stimulation; combined with forced hyperventilation, this may increase seizure risk and cardiovascular strain.
- →SupplementsCitrullineTheoreticalSerious
Citrulline increases nitric oxide and vasodilation, while hyperventilation can constrict cerebral blood vessels and may cause fainting; together, these effects may increase the risk of severe low blood pressure and fainting.
- →CaffeineTheoreticalCaution
Caffeine may amplify sympathetic overdrive during Wim Hof breathing, increasing the risk of a fast heart rate, high blood pressure, or arrhythmia.
- →Hormonal Cancer TherapyTheoreticalCaution
Estrogen lowering may impair cerebrovascular autoregulation; paired with blood-gas fluctuations during Wim Hof breathing, this may increase the risk of fainting or stroke.
Where the evidence comes from
- Reference knowledge
Open Hormonal Cancer TherapyConfidence
confidence 65/100
Okay to combine with
Highest probability of useful synergy
- →PracticesCold ShowerCertaintyMediumSourceReference knowledgePotentiating
Pairing cold exposure with breathing can amplify catecholamine release and brown fat activation, with potential metabolic and anti-inflammatory effects.
- →PracticesMeditationCertaintyMediumSourceReference knowledgeComplementary
Meditative focus can help with control over breath cycles and interoceptive awareness, deepening the physiological effects of breathing practice.
- →PracticesResonance Frequency BreathingCertaintyMediumSourceReference knowledgeComplementary
Slow-paced breathing after Wim Hof sessions may help stabilize the autonomic rebound and prolong vagal enhancement.
Where the evidence comes from
- Reference knowledge
Open Resonance Frequency BreathingConfidence
confidence 65/100
- →SupplementsMagnesiumCertaintyMediumSourceReference knowledgeComplementary
Magnesium supports neuromuscular relaxation and may counter heightened excitability, which can reduce cramp or tetany risk.
Weakens or is weakened by
Highest probability
- →SupplementsBeta-AlanineCertaintyMediumSourceReference knowledgeCompetitive
Beta-Alanine can cause tingling that may be intensified or mistaken for hyperventilation-related symptoms during the breathing practice, increasing discomfort and the risk of misinterpretation.
- →SupplementsAshwagandhaCertaintyMediumSourceReference knowledgeCompetitive
Ashwagandha’s sedative and anxiety-reducing effects may blunt the acute stress response induced by the breathing practice, potentially reducing the hormetic adaptation underlying its benefits.
- →PracticesBreathworkCertaintyMediumSourceTheoreticalCompetitive
Combining this practice with other intense breathwork techniques, such as holotropic breathing or rebirthing, may increase the risk of hyperventilation syndrome and loss of consciousness.
How it works
The mechanisms this practice works through16 listed · 0 established- Blood pHRespiratory alkalosisproposed
Hyperventilation induces hypocapnia, driving the reaction H+ + HCO3- ↔ H2CO3 ↔ H2O + CO2 to the right, elevating blood pH. Estimated arterial pH increase of +0.171 in WHBM condition.
- Connectedness to Nature Scale (CNS)Nature connectednessproposed
Longer WHM practice associated with greater nature connectedness, which mediates wellbeing.
- Epinephrine releaseSympathetic nervous system activationproposed
WHM increases epinephrine levels, which may trigger anti-inflammatory responses.
- Forced vital capacity (FVC)Respiratory functionproposed
The study found a statistically significant improvement in FVC following the 4-week WHM intervention.
- Interleukin-10Anti-inflammatory cytokine productionproposed
Increased epinephrine leads to increased IL-10 and decreased pro-inflammatory cytokines.
- Intermittent hypoxia and cold exposureHormetic stress responseproposed
The WHM breathing technique induces intermittent hypoxia and cold showers, which may promote stress resilience through hormetic mechanisms.
- Lactate and pyruvateMetabolic modulationproposed
Lactate and pyruvate may enhance IL-10 production and reduce pro-inflammatory cytokines.
- Melatonin secretionHormonal systemproposed
WHM training may improve the adaptability of the hormonal system to respond adequately to circadian rhythm changes, as indicated by significantly lower melatonin levels in the intervention group.
- Nijmegen Hyperventilation Syndrome Questionnaire sumscoreHyperventilation symptomsproposed
The hyperventilation sumscore significantly decreased following the intervention.
- Oxygen saturationHypoxemiaproposed
Oxygen saturation dropped to severe hypoxemia levels (60 ± 12%) at the end of the last breath-hold.
- Pittsburgh Sleep Quality Index (PSQI)Sleep qualityproposed
Sleep quality showed a significant improvement as measured by the PSQI.
- Spleen contractionDiving responseproposed
Breath-holding triggers the diving response including bradycardia, peripheral vasoconstriction, increased blood pressure, and contraction of the spleen, releasing stored erythrocytes into circulation.
- Stress regulationAllostatic loadproposed
Repeated exposure to controlled stress may modulate allostatic load and improve stress handling.
- Stress responseHormesisproposed
Intentional short-term stress induced by cyclic hyperventilation and cold exposure may enhance resilience through hormetic mechanisms.
- Sympathetic activityAutonomic nervous systemproposed
The WHM breathing showed significant elevations in sympathetic activity during lab monitoring.
- Wellbeing (WEMWBS)Psychological wellbeingproposed
WHM practice associated with higher wellbeing compared to population benchmarks.
Variations
5 documentedTypical protocol
7 protocolsEstimatedAcross every study of this practice, whatever the variation.
20 min · 7×/week
- Course
- 4 weeks
- Per week
- 123 min
- Temperature
- 14.1 °C
- Rounds
- 3
- Intensity
- High
- Format
- Individual
- Supervision
- Self-guided
Courses and single sessions · 6 repeated-course and 1 single-session protocols
78% of the corpus contributed
Standard 4-Round Breathwork
Intermediate9/1015–20 min · Daily
Standard 4-Round Breathwork
Intermediate9/1015–20 min · Daily15–20 min · Daily
Editorial- How often
- Daily
- Intensity
- High
- Time of day
- Morning
- Where
- Indoors
- Research depth
- Minimal
This version uses 30 rhythmic breaths followed by an exhale hold and a 15-second recovery hold, repeated for 4 rounds. It is intended for intermediate practitioners who are comfortable with breath holds.
No equipment needed.
not for children,not in pregnancy,caution for older adults
How it's done5 steps · 3 cues · 3 common mistakes
A general description of the practice, not instruction or medical advice.
Steps
- Lie down in a comfortable supine position on a mat or bed.
- Take 30 deep, rhythmic breaths: inhale fully through the nose or mouth, then passively exhale without forcing the air out.
- After the 30th exhalation, exhale completely and hold your breath for as long as you comfortably can.
- When the urge to breathe becomes strong, take a deep recovery inhale and hold it for 15 seconds, then exhale.
- Repeat this cycle for a total of 4 rounds.
Cues
- · Keep the inhale-exhale rhythm steady, like a wave.
- · Relax the body completely during the breath hold.
- · Don't force the exhale; let it fall out naturally.
Common mistakes
- Forcing the breath hold beyond a comfortable urge to breathe.
- Tensing the shoulders and neck during hyperventilation.
- Practicing in a position where falling asleep or fainting could cause injury.
Guided Audio Session
Beginner8/1012–15 min · Daily
Guided Audio Session
Beginner8/1012–15 min · Daily12–15 min · Daily
Editorial- How often
- Daily
- Intensity
- High
- Time of day
- Any time
- Where
- Indoors
- Research depth
- Minimal
A recorded instructor paces the breathing and breath holds, typically across 3-4 rounds in a session often 15 minutes long. This format may suit beginners or people who prefer external timing guidance.
No equipment needed.
not for children,not in pregnancy,caution for older adults
How it's done6 steps · 3 cues · 3 common mistakes
A general description of the practice, not instruction or medical advice.
Steps
- Find a quiet, safe place to lie down or sit comfortably.
- Play the guided Wim Hof breathing audio track.
- Follow the instructor's pacing for 30-40 deep breaths per round.
- Hold your breath on the exhale when instructed, releasing when prompted.
- Take the recovery breath and hold as directed by the audio cue.
- Complete the full session as guided, typically 3-4 rounds.
Cues
- · Let the audio pace your breathing; don't rush ahead.
- · Keep your eyes closed to minimize distractions.
- · Surrender to the process without overthinking.
Common mistakes
- Practicing while driving or in water.
- Comparing your breath-hold times to others.
- Stopping early due to tingling sensations, which are normal.
Instructor-Led Group Session
Beginner7/10supervision recommended25–30 min · Weekly
Instructor-Led Group Session
Beginner7/10supervision recommended25–30 min · Weekly25–30 min · Weekly
Editorial- How often
- Weekly
- Intensity
- Moderate
- Time of day
- Any time
- Where
- Indoors
- Research depth
- Minimal
This is a supervised group session, typically lasting 30 minutes, with instructor guidance and mindset coaching between rounds. The instructor may adapt the breath holds, and participants are asked to communicate discomfort and relevant health conditions.
No equipment needed.
not in pregnancy
How it's done5 steps · 3 cues · 3 common mistakes
A general description of the practice, not instruction or medical advice.
Steps
- Attend a session led by a certified Wim Hof Method instructor.
- Follow the instructor's verbal guidance for breathing cadence and retention.
- Participate in the group mindset and focus exercises integrated between rounds.
- Communicate any discomfort immediately to the instructor.
- Complete the full session as structured by the instructor, which may include modified breath holds.
Cues
- · Feed off the collective energy of the group.
- · Listen to your body first, the instructor second.
- · There is no competition; everyone's practice is their own.
Common mistakes
- Pushing past warning signs like severe dizziness to keep up with the group.
- Not informing the instructor of pre-existing health conditions beforehand.
- Assuming the group setting replaces the need for a daily home practice.
Studied protocols1 on file
- 30 min· 1×/week· 4 weeks· n=10· A repeated coursePMID 37754643
Metronome-Paced Precision
Intermediate7/1015–20 min · Daily
Metronome-Paced Precision
Intermediate7/1015–20 min · Daily15–20 min · Daily
Editorial- How often
- Daily
- Intensity
- High
- Time of day
- Morning
- Where
- Indoors
- Research depth
- Minimal
A metronome set to 20 beats per minute sets the breathing pace: inhale on one beat and exhale on the next for 30 breaths, repeated for 4 rounds. The metronome is used during the breathing phase, not the breath hold.
Equipment: Metronome (app or device)
not for children,not in pregnancy,caution for older adults
How it's done6 steps · 3 cues · 3 common mistakes
A general description of the practice, not instruction or medical advice.
Steps
- Set a metronome to 20 beats per minute.
- Lie supine and synchronize your breathing to the metronome: inhale on one beat, exhale on the next.
- Complete 30 full breaths at this exact pace.
- After the final exhale, turn off or ignore the metronome and hold your breath.
- Take a recovery inhale and hold for 15 seconds.
- Repeat for 4 rounds, maintaining the metronome pace only during the active breathing phase.
Cues
- · Match the breath cycle precisely to the tick-tock rhythm.
- · Maintain a relaxed face and jaw despite the pacing.
- · Use the metronome as a focusing tool, not a stressor.
Common mistakes
- Shallow chest breathing instead of full diaphragmatic breaths.
- Getting distracted by the metronome and losing the breath hold focus.
- Setting a metronome pace that is too fast or too slow for comfort.
Single-Exposure Performance Prep
Advanced6/1010–12 min · As needed
Single-Exposure Performance Prep
Advanced6/1010–12 min · As needed10–12 min · As needed
Editorial- How often
- As needed
- Intensity
- Very high
- Time of day
- First half of the day
- Where
- Indoors
- Research depth
- Minimal
This is a brief performance-focused version: 3 rapid rounds followed immediately by a physical or mental challenge, rather than a daily wellness routine. It is intended for advanced users familiar with their responses.
No equipment needed.
not for children,not in pregnancy,caution for older adults
How it's done6 steps · 3 cues · 3 common mistakes
A general description of the practice, not instruction or medical advice.
Steps
- Sit in a stable, upright position where you won't fall.
- Perform 30 rapid, full inhales and passive exhales.
- Exhale completely and hold until a strong, clear urge to breathe arises.
- Inhale deeply and hold for 10-15 seconds, then release.
- Repeat for exactly 3 rounds total.
- Immediately proceed to your performance task.
Cues
- · Focus on a powerful, diaphragmatic inhale.
- · Stay mentally present; do not dissociate.
- · The goal is activation, not relaxation.
Common mistakes
- Using this protocol for general relaxation instead of performance priming.
- Holding the breath to the point of blackout.
- Practicing on a full stomach.
Studied protocols2 on file
- 15 min· 7×/week· 2.1 weeks· 14.1 °C, Rounds 3· n=42· A repeated coursePMID 37845341
- n=132PMID 41661868
How to start
Community experience
Based on 350 public posts from Reddit, YouTube, Bluesky, and Hacker News.
What people report it did
34 outcomes mentioned across 350 public reports. A report often mentions several, so these counts do not add up to the total.
Reported benefits19
- Anxiety Reduction86 mentions
- Mood Improvement64 mentions
- Physical Energy Increase29 mentions
- Sleep Quality Improvement27 mentions
- Stress Resilience Improvement19 mentions
- Concentration Improvement16 mentionsnot studied
- Emotional Regulation Improvement14 mentionsnot studied
- Present Moment Awareness14 mentionsnot studied
- Cognitive Function Improvement13 mentions
- Muscle Relaxation7 mentions
- Interoception Improvement7 mentionsnot studied
- Vagal Tone Improvement7 mentions
- Immune System Support7 mentions
- Brain Fog Reduction6 mentionsnot studied
- Biorhythm Regulation6 mentionsnot studied
- Emotional Processing Support6 mentionsnot studied
- Physical Function5 mentionsnot studied
- Inflammation Reduction5 mentions
- Cellular Energy Support5 mentionsnot studied
Reported side effects14
- Dizziness14 mentions
- Anxiety Increase9 mentions
- Paresthesia (Tingling/Numbness)7 mentions
- Pain5 mentionsnot studied
- Fainting (Syncope)5 mentions
- Tinnitus Onset5 mentionsnot studied
- Digestive Discomfortnot studied
- Mental Fatiguenot studied
- Headachenot studied
- Inflammation Increasenot studied
- Insomnianot studied
- Irritabilitynot studied
- Muscle Tensionnot studied
- Panic Attacknot studied
Reported after stopping1
- Motivation Decreasenot studied
What people report doing
Counted from public posts and videos, not from a survey. Each figure counts the posts that mentioned it — most reports say nothing about schedule.
How often2 mentions
Session lengthas written
How long they've practisedas written
References
9 screened · 9 analysed · 10 listed below
Studies and sources cited on this page. Evidence quality varies — check the grade on each.
- Wellbeing, nature connection and vaccine attitudes: A convergent mixed methods study in Wim Hof Method practitioners.PLOS Ment Health2025Observational Cross SectionalCn=132
- A semi-randomised control trial assessing psychophysiological effects of breathwork and cold immersion.Sci Rep2025RCTCn=404
- A randomized controlled clinical trial of a Wim Hof Method intervention in women with high depressive symptoms.Compr Psychoneuroendocrinol2024RCTCn=84
- Does the Wim Hof Method have a beneficial impact on physiological and psychological outcomes in healthy and non-healthy participants? A systematic review.PLoS One2024Systematic reviewC
- The effectiveness of the Wim Hof method on cardiac autonomic function, blood pressure, arterial compliance, and different psychological parameters.Sci Rep2023RCTCn=42
- Does Wim Hof Method Improve Breathing Economy during Exercise?J Clin Med2022RCTCn=19
- Acute Effects of the Wim Hof Breathing Method on Repeated Sprint Ability: A Pilot Study.Front Sports Act Living2021Crossover RCTCn=15
- The Effect of Mindset and Breathing Exercises on Physical and Mental Health in Persons with Spinal Cord Injury-A Pilot Feasibility Study.Int J Environ Res Public Health2023Pilot studyDn=10
- A novel Wim Hof psychophysiological training program to reduce stress responses during an Antarctic expedition.J Int Med Res2022Observational CohortDn=13
- Expert knowledge synthesis