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The Nuance
‘Biofeedback’ Could Ease Headaches, Anxiety — and Maybe a Lot Else
By providing a window onto the body’s inner workings, biofeedback could help people control what was once thought to be ungovernable
The man’s boasts were outlandish. Wim Hof, a 51-year-old Dutch endurance athlete, claimed that he could voluntarily control his own immune system — ramping its activity up or down at will. Moreover, he said that he could teach this skill to others.
Hof’s assertions might never have been put to the test but for the fact that he held several remarkable world records — including one for the longest time spent submerged neck-deep in an ice bath, and another for the fastest half marathon run barefoot on snow. His accomplishments earned him the nickname “the Iceman” and generated enough public interest — at least in the Netherlands — that scientists decided to investigate his claims.
For a 2012 study that appeared in the journal Psychosomatic Medicine, a team of Dutch researchers injected Hof with a toxin from E. coli bacteria. In past experiments, the toxin had reliably caused nausea and other symptoms and had also produced steep elevations in blood biomarkers of inflammation. After receiving the injection, Hof reported almost no symptoms, and his blood samples revealed “a remarkably mild inflammatory response,” the study authors reported.
In 2014, a follow-up study repeated the experiment using a group of 12 people who had trained using Hof’s methods. Blood samples indicated that, like Hof, they were able to exert some control over their body’s inflammatory response, which is a component of the immune system usually thought to be wholly involuntary and that, when overactive, can cause or contribute to a wide range of health problems.
“Hof had effectively found the off-switch for his immune system,” says Scott Carney, an investigative journalist who details his own experience with Hof’s…
