Scientific literature said it was impossible, but RadboudUMC researchers have now proven that it is possible voluntarily to influence both the autonomic nervous system and the immune system.

In 2011 the same researchers monitored the response of Iceman Wim Hof's body to an endotoxin injection as he performed the techniques he had developed himself. It turned out that he produced half the amount of inflammatory proteins healthy volunteers did who did not master his method. Moreover, he hardly showed any influenza symptoms. It seemed that he could suppress his immune response through the autonomic nervous system. But since one finding in one individual does not constitute scientific evidence, the scientists decided to do a follow-up study. For that reason, in 2013, studies were performed on a group of young, healthy, male volunteers: and, indeed, it turns out they are able to influence both the autonomic nervous system and the immune system.