Possible Causes of Flatulence

Commonly referred to as "passing gas," "farting," "breaking wind" and any number of other popular slang terms, flatulence is the act of expelling intestinal gas, or flatus, from the rectum. It can be quite an embarrassing occurrence, but the average person passes gas at least a few times a day. A number of factors can contribute to the buildup and expulsion of flatus.

Food

• Probably the most common cause of flatulence, ingested food that does not fully break down before entering the large intestine stimulates the production of flatus. The intestine releases bacteria to essentially ferment this undigested food, creating intestinal gas as a byproduct. Some foods, including beans, lentils, potatoes, corn, wheat and most fruits, contain elements that are notoriously hard to break down in the upper digestive tract, and commonly lead to flatus production in the lower intestine. In addition, dairy products are a huge lower intestinal gas producer in people who are lactose intolerant.

Swallowing

• When we eat, drink, cough, hiccup and chew we almost always swallow tiny amounts of air. While most of this swallowed air comes back up in the form of a burp, it can sometimes make its way into the digestive tract. This small amount of air eventually becomes part of the gas mixture in flatus.

Medical Conditions

• There are a number of medical conditions that may contribute to excessive flatulence. For instance, celiac disease causes an immune response in the small intestine when food containing gluten is eaten. This reaction damages the small intestine's ability to absorb nutrients, sometimes leading to gas production in the large intestine. Dumping syndrome is a condition in which the stomach prematurely releases food to the intestinal tract, also leading to flatulence. Other conditions and disorders that often lead to excessive flatulence include irritable bowel syndrome, food allergies, peptic ulcers, gastroparesis, gastroesophageal reflux disease and short bowel syndrome.

High Altitude Flatus Expulsion

• High altitude flatus expulsion (HAFE) is an occurrence commonly experienced by high-altitude hikers and mountain climbers. With an increase in elevation comes a decrease in atmospheric pressure. The pressure created by the intestinal gases becomes much higher, relative to the external pressure, creating the urge to pass gas. This causes an increase in both the frequency and the volume of flatulence. In many cases HAFE causes spontaneous and uncontrollable flatulence. However, there is some evidence that a high-carbohydrate diet can decrease the effects of HAFE.