Updated June 3, 2013
Inflammatory bowel diseases occur almost exclusively in parts of the world where the diet is high in meat and dairy foods, and are rare in countries where people still consume starch based, almost entirely vegetarian meals. Severe “allergic-type” reactions to some of those rich foods have been suspected as being the causes of these conditions.
Some clustering of cases in a family occurs, which is consistent with the fact that we learn our food preferences from our parents.
Current Treatment: Bowel contents must be changed continually in order to get long lasting significant improvement. The simple increase of the fiber content in the foods eaten has been shown to reduce the frequency of attacks and to improve symptoms in many patients. A starch-based diet, which is inherently high in fiber, is highly effective at alleviating the distress from this condition.
One step further in effective therapy is to avoid the foods that most often cause allergies–dairy products, eggs, chocolate, wheat, and citrus fruits, as well as fats of all kinds. If this approach is not successful, the final step toward diagnosis is to use an elimination diet. (For elimination diet see Allergic Reactions to Food.)
An important study was performed with Crohn’s disease patients who had been suffering from severe diarrhea for many years, with 20 stools or more per day. The subjects were changed from a high fat diet to one low in fats. This gave relief from the frequent watery stools within two to three days. Most patients continued to form solid bowel movements-as long as they kept the animal and vegetable fats out of their diet.
A person with a functioning healthy small intestine re-absorbs the bile secretes from the liver in the last part of the small intestine, called the ileum. In patients with Crohn’s disease this portion of the ileum often is damaged and unable to absorb the bile. Bile continues to flow along the ileum into the large intestine, where it causes irritation and discharge of mucus and water. In these patients the immediate benefit from a change in diet is the decrease in bile acids produced by the liver as a response to lowering the fat content of the foods eaten. In addition, the fibers introduced in a plant based diet bind and neutralize many of the bile acids and absorb free water present in the stool.
The benefits for ulcerative colitis patients are equally dramatic. A dietary approach to this disease has been successful. A large series of patients improved, and many were actually cured of this serious condition by simply removing milk (dairy proteins) from their diet. Other investigators have approached this problem from the broader therapy of eliminating many sources of common food allergens, and have shown great success with their patients-and no side effects.
Another strong reason to change the diet of someone suffering from inflammatory bowel disease is that the high-fat, high-cholesterol, low fiber American diet increases the risk of developing cancer of the colon. People with inflammatory bowel diseases are at greater risk than is the average American, lucky enough to have a healthy intestinal tract.
For a person with Crohn’s disease or ulcerative colitis, who must endure pain and diarrhea every day, the option of choosing a simple meal plan is not a difficult one, especially when the penalty for making the occasional mistake of submitting to temptation from a rich repast is so immediately evident.
Patients who are very ill may need to be put on very simple diets, supplemented with some drugs until the bowel quiets down. As soon as the patient can eat regular foods comfortably, he should be started on a starch-centered diet without wheat or citrus fruits initially (later these two kinds of plant foods may be tried). The elimination diet is the next approach for stubborn cases.
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