Your Gastrocolic Reflex With IBS

You may have wondered why you feel the urge to have a bowel movement soon after eating—especially if you have irritable bowel syndrome (IBS). It's due to the gastrocolic reflex, a physiologic response in which the simple act of eating stimulates movement in the gastrointestinal tract. This reflex is natural but is abnormally strong in those with IBS, and it has been implicated as playing a part in some of the symptoms of the condition.

Symptoms of an abnormally strong gastrocolic reflex may include cramping, a sudden urge to move your bowels, and in some people, diarrhea.

Let's take a look at what factors increase the strength of the gastrocolic reflex, what this means for a person for IBS, and how you can use this information to address your own digestive symptoms.

Research indicates that a significant number of people who have IBS have an exaggerated gastrocolic reflex action in response to meals. This reactivity appears to be the result, at least in part, to abnormal levels of the hormones cholecystokinin (CCK) and motilin, both of which are responsible for regulating the motility of the digestive system.

This exaggerated response can manifest itself in worsened symptoms occurring soon after eating—what doctors call postprandial symptoms.

The reflex is triggered by the act of eating, but there are other factors that impact how strong the intestinal contractions are. The following things can cause these contractions to increase in intensity:

• Eating a large meal
• Eating a meal that contains unhealthy forms of fat, such as fried foods, fatty meats, and rich gravies
• Drinking large amounts of cold liquid at one time

In addition, people who are sensitive to lactose-containing foods, or other high FODMAP foods may experience worsened symptoms after eating these foods.

If you have diarrhea-predominant IBS (IBS-D), you can use your new knowledge about the gastrocolic reflex to try to reduce its effect on your symptoms:

• Try to eat smaller meals, avoiding foods that contain unhealthy types of fat, or any foods that cause increased gas, bloating, or diarrhea.
• Before eating, sip some peppermint tea or take a peppermint oil supplement, both of which have antispasmodic effects.
• If your doctor has prescribed you an antispasmodic medication, you may find that taking the medication approximately 20 minutes before eating can help to reduce any postprandial cramping and pain.

Conversely, if you find that you experience chronic constipation, you can perhaps use the gastrocolic reflex to your advantage. For most people, natural body rhythms are such that the urge to have a bowel movement is strongest in the morning. Making sure to eat a large breakfast, with some foods with healthy fat, may strengthen your gastrocolic reflex and help to initiate a morning bowel movement.