Scientists believe that Crohn disease is caused by environmental factors
triggering an abnormal immune response of the gut mucosa in genetically susceptible
individuals. Now, French researchers have proposed that certain types of bacteria
that survive in refrigerated food may play a role in the disorder, and that
the emergence of the disease in the latter half of the 20th century was related
to the availability of modern refrigeration (Lancet. 2003;362:2012-2015).
Stephenson J. Cold Conjecture. JAMA. 2004;291(3):291. doi:10.1001/jama.291.3.291-d