Irritable bowel syndrome, or IBS, is one of the most common gastrointestinal conditions. Estimates suggest that between 30 million to 45 million people in North America have IBS, according to an article in the January 2009 issue of "The American Journal of Gastroenterology." People with IBS may experience gas and bloating. Understanding the mechanism and treatments may help improve these symptoms.
Gas Production
Gas is produced from bacteria fermenting nutrients in the colon --- a very complex process. A widely held belief is that excessive gas production in the digestive tract leads to bloating and flatulence. A study in the October 10, 1998 issue of "Lancet" found more hydrogen in the colons, or large intestines, of people with IBS compared with people without the condition. The researchers concluded that fermentation from bacteria of food material in the colon seems to be an important contributor to IBS. A review of research in the 2002 issue of the "Journal of Clinical Gastroenterology" noted, however, that the "Lancet" study was only one small investigation, so more research is needed before concluding that people with IBS produce more intestinal gas.
Role of Fiber
Fiber plays a contradictory role in gas and bloating in people with IBS. According to the "Journal of Clinical Gastroenterology," gas and bloating may worsen after eating fiber, particularly insoluble fiber. A gradual increase of fiber intake --- especially foods with soluble fiber --- may alleviate gas and bloating, however. Soluble fiber is found in such foods as citrus fruits and oats. Insoluble fiber is in many whole grains. The effect of fiber on gas and bloating seems to vary among people with IBS. People experiencing gas and bloating from fiber are advised to reduce their consumption of foods containing fiber.
Sensitivity to Fat
People with IBS may experience excessive gas and bloating after eating fatty foods. The gas and bloating may be caused by an increased intestinal sensitivity to fat among people with IBS, according to a study in the January 2001 issue of "Gut." Reducing fat intake is recommended for those who experience gas and bloating after eating fatty foods to help reduce their discomfort.
Undigested Carbohydrates
People with IBS may experience gas and bloating after eating foods containing lactose, fructose and sugar alcohols, such as sorbitol, mannitol, and xylitol, according to the "Journal of the American Dietetic Association." Lactose is found in milk products and many baked goods and fructose is in high-fructose corn syrup, honey and some fruits. Sugar alcohols are found in liquid medications and diet and "sugar-free" products. These carbohydrates are not absorbed fully in the digestive tract, thus leading to gas and bloating from bacteria fermenting the undigested substances in the colon. Reduced intake of these carbohydrates is recommended to reduce IBS symptoms.
Recommended Diet
No one specific diet has been shown to be effective in improving IBS symptoms of gas and bloating, according to the "Journal of Clinical Gastroenterology." Food contributors to gas and bloating differ among people with IBS. Determining troublesome foods often helps in establishing an individualized eating plan to improve IBS symptoms.
References
- "American Journal of Gastroenterology"; Systematic Review on the Management of Irritable Bowel Syndrome in North America; Lawrence Brandt, M.D., David Bjorkman, M.D., Brian Fennerty, M.D., G. Richard Locke, M.D., Kevin Olden, M.D., Water Peterson, M.D., Eamonn Quigley, M.D., Philip Schoenfeld, M.D., Marvin Schuster, M.D., and Nicholas Talley, M.D., Ph.D.; January 2009.
- "Gut"; Impaired Transit and Tolerance of Intestinal Gas in the Irritable Bowel Syndrome; Jordi Serra, M.D., Fernando Azpiroz, M.D., and Juan --R. Malagelada, M.D. January 2001.
- "Journal of the American Dietetic Association"; The Role of Diet in Symptoms of Irritable Bowel Syndrome In Adults: A Narrative Review; William Heizer, M.D., Susannah Southern, and Susan McGovern; July 2009.
- "Lancet"; Abnormal Colonic Fermentation in Irritable Bowel Syndrome; Tim King, M.D., Marinos Elia, M.D., and John Hunter, M.D.; October 10, 1998.
