Irritable Bowel Syndrome-IBS

Information, Diet Suggestions, and Resources

What is Irritable Bowel Syndrome-IBS?

Irritable Bowel Syndrome (IBS) is a condition with symptoms including chronic abdominal pain, diarrhea or constipation, gas and/or bloating. IBS does not cause an inflammatory or structural abnormality of the gastrointestinal tract. The onset of IBS may follow an infection. Other causes of IBS include motility abnormalities in the gut, hypersensitivity to stretching of the gut wall or to gut contents, a change in the gut bacteria, or a change in the immune cells in the gut. In the United States, IBS affects women twice as often as men.

The Diets

The dietary treatment for Irritable Bowel Syndrome varies from patient to patient. However, recent scientific studies have shown that a low FODMAP diet can greatly improve symptoms. The specific carbohydrate diet is advocated by some for IBS although scientific studies to date are lacking.

-The Low FODMAP Diet, for patients who have increased gas from the difficulty of digesting complex carbohydrates. This diet avoids foods that are high in FODMAPs (fermentable oligosaccharide, disaccharide, monosaccharide and polyols), such as some fruits, vegetables, nuts, seeds, grains and grain-based products, dairy and dairy alternatives, sugars and sweeteners. The low digestibility of FODMAPs results in their poor absorption in the small intestine. In this case, when eaten, the food passes undigested from the small intestine to the large intestine, where it is fermented by bacteria. This can lead to symptoms including gas, bloating, abdominal discomfort, pain and altered bowel function. The low FODMAP diet includes foods such as some fruits (for example-bananas, blueberries, and pineapple), vegetables (for example-tomatoes, green beans, and potatoes), some nuts, seeds, grains and grain-based products, some dairy and dairy alternatives, and sugars and sweeteners that are low in fermentable oligosaccharide, disaccharide, monosaccharide and polyols. This diet has been successful for many IBS patients and has been shown to be beneficial in a well-performed scientific study.

-The Specific Carbohydrate Diet (SCD), which restricts complex carbohydrates, such as sugars, in the diet. Complex carbohydrates are not easily digested and when eaten, the food passes undigested from the small intestine to the large intestine, where it is fermented by bacteria. This can lead to IBS-like symptoms including gas, bloating, abdominal discomfort, pain and altered bowel function. The carbohydrates that are allowed in the SCD are monosaccharides that can be easily absorbed by the intestinal wall, such as apples, apricots, bananas, peppers and broccoli. This diet has been successful for many IBS patients, but has not been confirmed for IBS in studies published in the medical literature.