Wim Hof cold water therapy benefits are not backed by quality science, report says
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A systematic review of scientific studies on the Wim Hof method of cold water therapy found the quality of the research inadequate to support most claims of effectiveness without addition investigation.
Wim Hof, a Dutch extreme athlete and motivational speaker, is well-known for his ability to withstand the cold.
“It must be noted that the quality of the studies is very low, meaning that all the results must be interpreted with caution,” according to the analysis published Wednesday in the journal PLOS One.
Hof attributes his success to his training method, which focuses on a commitment to practicing cold water therapy with a specific form of breathing. The training reduces stress, improves sleep, bolsters the immune system, and increases energy, focus and willpower, according to Hof.
While some research did hint at “promising” anti-inflammatory effects from a combination of cold water immersion and the Wim Hof method of breathing, “more research of higher quality” would be needed to verify that finding, the researchers noted.
“As revealed by the review, the science is too weak/biased to conclude what the Wim Hof method achieves,” said cold water survival expert Mike Tipton, professor of human and applied physiology at the University of Portsmouth in the United Kingdom, in an email. He was not involved in the study.
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Wim Hof has broken his own record of sitting in ice water for hours at a time.
Known as “The Iceman,” Hof has swum under ice for 66 meters (72 yards), run a half-marathon barefoot in the snow and climbed Mount Everest without a shirt on. According to the Guinness World Records Hall of Fame, Hof has earned 18 Guinness World Records titles, often beating his own records to do so.
Other health benefits listed on Hof’s website, which have not undergone scientific validation in large, clinical trials, include increasing sports performance, reducing recovery time after workouts, improving blood pressure, providing pain relief, boosting the body’s metabolism, overcoming multiple sclerosis, and providing relief from arthritis, asthma, autoimmune disease, fibromyalgia and post-treatment Lyme disease syndrome.
The review examined eight randomized clinical trials — considered the gold standard of research — but found the small sample size ranging from 13 to 40 mostly male participants in each study hindered the ability to generalize the results to other populations.
In addition, Tipton said, studies in the review did not compare the impact of ice water with any other physical activity such as indoor swimming, yoga or walking.
“We have no idea what, if any, ‘active ingredient’ is in the Wim Hof method. We have no idea if any benefits arising from the Wim Hof method could not be obtained more safely by other means,” Tifton said. “I do not agree that anyone can do things like cold water immersion.”
Submerging the body in cold water is not advised for a range of medical conditions, Tipton said. Those include asthma, high blood pressure, cardiac rhythm disturbances or any heart disease, unstable diabetes, seizure disorders such as epilepsy, and a family history of sudden or unexplained cardiac death.
“We acknowledge the need for more high-quality research to substantiate the Wim Hof Method’s promising effects,” a spokesperson for Hof told CNN via email. “It’s our ongoing commitment to collaborate with the scientific community to conduct larger, more inclusive studies that address these concerns.”
Cold water drains heat from the body up to four times faster than cold air, according to the National Weather Service. “When your body hits cold water, ‘cold shock’ can cause dramatic changes in breathing, heart rate and blood pressure,” the service’s website says. “The sudden gasp and rapid breathing alone (create) a greater risk of drowning even for confident swimmers in calm waters.”
Wim Hof cold water therapy benefits are not backed by quality science, report says