Diet, food and eating can affect symptoms in IBS. Many people with irritable bowel syndrome (IBS) notice that their symptoms appear to get worse following a meal. They may wonder if they have a dietary allergy or intolerance. More confusing, they may notice that a food seems to upset them on one day but not another.

Among the most common questions IBS patients have is what food to avoid. This can drive a person to go looking for a diet or a test that might help sort all this out. A bewildering amount of often conflicting advice is available, especially on the Internet. Much of it is associated with a considerable cost.

Video with Peter Whorwell, MD

Diet, Eating and IBS Symptoms

There are a variety of factors that affect IBS, and diet is just one of these. If other factors, such as stressors or hormonal changes, are more active on a particular day, then dietary triggers are more likely to push your symptoms "over the edge."

There is no evidence that digestion of food is different in those with IBS compared to those without IBS. Diet, food and eating do not cause IBS.

However, muscles and nerves are over-reactive in IBS. This can cause the bowel to over-respond to stimuli.

Even a normal event such as the act of eating itself, and not a particular food, may aggravate symptoms at times. Eating releases hormones that stimulate the gut.

Adapted from IFFGD Publication #220 by Peter J. Whorwell, MD, Professor of Medicine and Gastroenterology, University of Manchester, Manchester, United Kingdom.