A recent published hypothesis proposed that Crohn's disease was provoked by 
infantile exposure to micro-organisms that can survive refrigerator temperature. 
A case-control study was accordingly devised. The mean age at first fridge was 
5.6 years amongst 88 patients with Crohn's disease, 5.5 years in 88 patients 
with ulcerative colitis (UC) and 7.6 years in 88 controls, but a majority of 
individuals had always been exposed to refrigerated food. Differences were more 
striking in subjects aged above the median (10.3, 10.9 and 15.0 years for 
Crohn's disease, UC and controls, respectively). This support for the hypothesis 
reached statistical significance for those with Crohn's disease compared to the 
controls (p=0.045).