One of the biggest mysteries surrounding inflammatory bowel disease (IBD) is why individuals who grew up in areas where it doesn't exist develop the disorder after moving to certain countries. New research suggests that the reason is a Western-type diet.
University of Chicago researchers found that consuming a diet high in saturated (milk-derived) fat kicks off a series of events. They can culminate in immune disorders like IBD in individuals who are genetically predisposed, according to the study published on Wednesday in the journal Nature.
The two most common types of IBD are Crohn's disease and ulcerative colitis. Researchers have been unable to find one definitive cause for either illness.
I am a patient with Crohn's disease, which has no cure. For many years, I've heard remarks about a dietary link between the disorder and eating a "rich" Western diet. The Mayo Clinic now recognizes that where you live is a risk factor for developing Crohn's. Those in industrialized countries or urban areas face a greater risk of the disorder. The conclusion is that environmental factors like a diet full of fat or refined foods play a role in developing this type of IBD.
The greatest significance of the Chicago research is that it marks the first time scientists have been able to track step-by-step how Western-type diets play a part in inflammatory bowel diseases, Newswise reports. The findings help shed some light on how these diseases -- once considered rare -- have become commonplace in westernized societies within the last 50 years. They also help explain why certain people otherwise at risk for IBD never develop it.
Researchers used a mouse model with many components similar to those of IBD in humans. They manipulated the mice to make them genetically susceptible to the inflammatory diseases. After they fed them a diet rich in saturated milk fats, the rate of disease development tripled within six months, to 60 percent. Symptoms in the affected mice were much more severe than those in the ones with low-fat diets.
The scientists also discovered a rare microbe linked to the diet high in milk fat. Earlier studies located the same bacteria in patients with appendicitis and inflammatory intestinal disorders like IBD. When these bacteria have access to sulfur, they thrive and can overactivate the immune system of patients with a genetic IBD predisposition.
The Mayo Clinic also cites a link between developing Crohn's disease and living in northern countries. Whether living in these regions creates genetic changes passed to future generations remains unproven. However, my ethnic background is 100 percent German.
My weight also stubbornly stays about 20 pounds above that in weight charts. When diagnosed, I was a far cry from the stereotypical thin, malnourished Crohn's patient. Perhaps the Western diet that put me at risk for IBD has made a body type like mine the stereotype today.
Vonda J. Sines has published thousands of print and online articles. She specializes in health and medical topics and has a particular interest in diseases and other factors that affect quality of life.
- Disease & Medical Conditions
- inflammatory bowel disease