Wim Hof Method: Origins, Claims and What Studies Found
A critical look at the Wim Hof Method: its three parts, who runs the studies, what small trials found on inflammation and mental health, and the safety limits.
Content last updated . This page has not been medically reviewed.
What it is
The Wim Hof Method (WHM) is a program named after Wim Hof, a Dutch man known as "the Iceman". [2] Researchers describe it as three parts: a breathing technique, cold exposure, and commitment or mindset. [3] The breathing part in the research is cyclic hyperventilation followed by breath retention. [4] A news report described the company's basic exercise as deep breathing followed by holding the breath, and described Hof's own videos as often showing cold water. [5] We do not describe the steps here, because the combination of fast breathing and breath-holding can cause fainting.Claims versus what was studied
Science news coverage reports that Wim Hof claims the method brings benefits including a "fortified" immune response and reduced inflammation, and says the jury is still out on whether it does. [5] Below, "promising but limited" means small studies point one way; it does not mean the method is proven.| Question | What the studies found | Label |
|---|---|---|
| Does it change the immune response? | In a 2014 randomized experiment, 24 healthy volunteers were split into trained and untrained groups. After a controlled injection of bacterial endotoxin, the trained group (12) had lower levels of some inflammatory markers and fewer flu-like symptoms [4] | Promising but limited (lab markers) |
| What does the review say overall? | A 2024 systematic review of eight trials suggested possible reduction in inflammation, with mixed findings for exercise performance [3] | Promising but limited |
| How good are those trials? | Warwick researchers who ran the review said the trials had small samples and high risk of bias in most, and that evidence for the breathing method alone is mixed [6] | Limited |
| Depression and stress | In 84 women with high stress and depressive symptoms, the WHM and a slow-breathing comparison produced equivalent reductions in depression, anxiety and stress. All dropouts were from the WHM group [7] | Mixed (no difference from slow breathing) |
| Energy and mental clarity | In a 2025 semi-randomized study of 404 healthy adults, WHM groups reported greater momentary improvements than a meditation group, but few differences in longer-term traits [8] | Promising but limited (self-reported) |
| Spinal cord injury | A 2026 randomized trial of 62 adults found no significant difference in mental health scores between groups [9] | No benefit shown for the main outcome |
| Multiple sclerosis | A small trial with data from 12 WHM and 13 no-intervention participants reported symptom score improvements [10] | Insufficient evidence (very small, no active comparison) |
Who ran the studies, and what limits them
These studies cannot be blinded: people know whether they are breathing and getting cold. Many compare with no intervention, so expectation may explain part of the result. In the 2014 experiment, the trained group was trained by Wim Hof and three trainers he had instructed, and Hof coached participants during the experiment days. [11] That is a conflict worth knowing about when reading results. In the women's depression trial, the control group thought their program was more credible and expected more benefit. [7] Most measures in the larger studies are self-reported. A change in a lab marker such as an inflammatory cytokine is a physiological finding, not a health outcome such as fewer infections.Teachers, training and cost
A research paper describes trainers who had received an instructor course from Wim Hof. [11] We did not find a government or professional-body regulation of WHM instructors in the sources we read, and a certificate does not guarantee safety. If you consider a class, ask about health screening, what they say about water and driving, and whether they discuss medical conditions first. We do not list instructors and have no verified price information. Related approaches are compared in Buteyko, Wim Hof and holotropic breathwork.Frequently asked questions
Does Wim Hof breathing boost immunity?
Proper evidence not found for better health outcomes. One small experiment changed lab markers after an endotoxin injection. [4][3]
Is the Wim Hof Method better than ordinary slow breathing?
In one trial of women with high stress, it produced equivalent reductions in depression, anxiety and stress to slow breathing with warm showers. [7]
Is it safe?
Its own website says it can rarely cause loss of consciousness and warns about water and driving. [1] No systematic harm study was found.
Can I do it before a cold plunge or in a pool?
No. Fast breathing and breath-holding in water have been linked to drownings. [5]
Is it the same as holotropic breathwork?
No. Both use deliberate fast breathing, but holotropic breathwork is a group session with music led by certified facilitators. [12] See Holotropic Breathwork: origins, claims and risks.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety first
This page does not teach the breathing. The method's own website says its intensive breathing can in rare cases lead to loss of consciousness, which can be very dangerous in or near water or when driving. [1] Deaths have been reported when people did this kind of breathing in water; see Wim Hof-style breathing and water. Talk with a clinician first if you have a heart condition, asthma or another lung condition, epilepsy, high or low blood pressure, are pregnant, or have a history of panic, psychosis, mania or trauma. If you faint, have chest pain, or cannot catch your breath, call 911 in the US.
Safety, beyond water
The 2014 experiment reported that practicing the techniques caused intermittent respiratory alkalosis (a shift in blood chemistry from over-breathing) and low oxygen. [4] Experts told Live Science that, besides drowning, Hof's cold-water demonstrations could cause irregular heart rhythms from the cold shock response. [5] For cold, see cold exposure plus breathwork claims and hydrotherapy safety. We found no systematic study of harms: proper evidence not found.
References
- Wim Hof Method, Breathing exercises page. Company website. Read 2026-10-22.
- DutchNews.nl, 'Iceman' Wim Hof cleared of causing death of American teenager. 3 July 2024. Read 2026-10-22.
- Does the Wim Hof Method have a beneficial impact on physiological and psychological outcomes? A systematic review. PLoS One 2024. Read 2026-10-22.
- Voluntary activation of the sympathetic nervous system and attenuation of the innate immune response in humans. PNAS 2014. Read 2026-10-22.
- Live Science, 'Gambling with your life': Experts weigh in on dangers of the Wim Hof method. Patrick Pester, 5 April 2024. Read 2026-10-22.
- University of Warwick press release, Does the Wim Hof method really work? (last revised 14 March 2024). Read 2026-10-22.
- Randomized controlled clinical trial of a Wim Hof Method intervention in women with high depressive symptoms. Compr Psychoneuroendocrinology 2024. Read 2026-10-22.
- Semi-randomised control trial assessing psychophysiological effects of breathwork and cold immersion. Sci Rep 2025. Read 2026-10-22.
- Breathing exercises and mindset with or without cold exposure in persons with spinal cord injury: randomized controlled trial. Clin Rehabil 2026. Read 2026-10-22.
- Cold exposure, breathing exercises and mindfulness training as complementary treatment in multiple sclerosis: pilot interventional study. Mult Scler Relat Disord 2025. Read 2026-10-22.
- PNAS 2014, full text and methods. Read 2026-10-22.
- Institute for Holotropics / Grof Transpersonal Training, Holotropic Breathwork. Practitioner organization website. Read 2026-10-22.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.