Certain bacterium that thrives in refrigerated food may be the cause of Crohn’s disease, an ailment of the digestive tract. At least half a million Americans suffer from Crohn's disease, an inflammatory bowel disease that causes abdominal pain, diarrhea, and potentially, bleeding and anemia. About 25% of people with Crohn’s or ulcerative colitis also experience either peripheral or spinal arthritis (spondylitis of inflammatory bowel disease).

Their theory suggests that food refrigeration is the catalyst for a dramatic increase in the number of Crohn’s cases in modern times. Many theories abound, but no single cause has been identified. It is thought to be caused by environmental factors (like lifestyle, smoking, diet) among people with a genetically susceptible predisposition.

In the December 13, 2003 issue of the journal The Lancet, widely respected Crohn's researcher Jean-Pierre Hugot, MD, and colleagues from Paris' Hospital Robert Debre point out that the arrival of mechanical refrigeration in kitchens throughout the industrialized world paralleled the rise in diagnosed cases of Crohn's disease.

But could modern refrigeration, considered as one of the most significant health advances of the 20th century, really cause this lifelong disease?

Dissecting the Evidence
This study’s researchers believe specific bacteria that thrive at low temperatures are the potential cause of Crohn's disease in genetically susceptible people, a theory they call the “cold chain hypothesis."

"The cold chain hypothesis suggests that psychotropic bacteria such as Yersinia and Listeria -- commonly found in beef, pork, chicken, sausages, hamburgers, cheese, and lettuce -- contribute to the disease," Hugot said in a news release.

A Curse of Modern Development
Crohn's expert David Sachar, MD, says it is widely believed that environmental changes during the 20th century have played a role in the rising prevalence of the disorder. He tells www.webmd.com that Hugot and colleagues make a good case for their theory that food refrigeration is the environmental catalyst researchers have been looking for, and adds that there is no group of researchers with better credentials to make such a claim.

But while Sachar says it is clear the researchers are "in the right church," it is not clear that they are "in the right pew."

"Their suggestion that the modern industrialized environment has introduced new bacteria into the food supply is not in itself novel," he believes.

"What is novel is their argument that it is refrigeration in particular that has promoted the emergence of causative bacteria in food. This is certainly a proposal worthy of serious consideration, but it may be no more plausible than parallel hypotheses linking the development of pathologic lesions to ingested small particles -- whether from food additives or packaging or cooking utensils or, for that matter, even from toothpaste."

Implications
Should the hypothesis be proven, researchers believe it could have implications for future Crohn's disease research. At this point, no one is suggesting that Crohn's patients should, or even could, avoid foods that have been refrigerated.

"(Refrigeration) has produced many benefits for western societies, including the prevention of enteric infections, allowing more people access to a well-balanced diet," Hugot and colleagues wrote. "These advantages clearly outweigh the putative risks discussed here."

Source -- Hugot, J. The Lancet, Dec, 13, 2003; vol. 362: pp. 2012-2015. Jean-Pierre Hugot, MD, Hospital Robert Debre, Paris, France. David B. Sachar, MD, FACP, clinical professor of medicine, director emeritus, Division of gastroenterology, Mount Sinai School of Medicine, New York City.