Some people with Crohn's are electing to be infected with parasitic hookworms instead.
In order to live as a parasite inside the human, the parasite must convince the host's immune system to chill and not try to reject it. With hookworms, they secrete a chemical that distracts the immune system, dampening down its response. Hookworms are common in undeveloped countries, places where inflammatory bowel disease is rare.
In the United States, thanks to advances in modern sanitation techniques, hookworms are rare but immune disorders on the rise.
Is there a connection? There could be. "As we have made things more hygienic," Dr. Terdiman explained, "we may in fact be precipitating an outbreak or an increase in the frequency of these immune disorders."
Worm Therapy is a company that uses hookworms and tapeworms to modulate the immune system. A single dose of hookworms costs $2,399 and tapeworms (used for weight loss, asthma and allergy) cost $1,299.
Mark Frauenfelder is the founder of Boing Boing and the editor-in-chief of MAKE and Cool Tools. Twitter: @frauenfelder. His new book is Maker Dad: Lunch Box Guitars, Antigravity Jars, and 22 Other Incredibly Cool Father-Daughter DIY Projects