Christian Stone, MD, Washington University gastroenterologist at Barnes-Jewish Hospital, says there''s nothing to be ashamed of. He says on average a person has a flatulatic occurrence nearly 10 times a day. "It''s normal to have gas," Dr. Stone says.

Some people may deny they have gas, but like it or not, Dr. Stone says everyone produces gas in the stomach and colon. A person swallows an average of one tablespoon of air per swallow when eating, drinking or chewing gum, which causes gas in the stomach and makes people burp. When carbohydrates such as lactose and large complexes of sugars reach the colon to be digested, bacteria that live in the organ break down the carbohydrates. However, in this process, a byproduct is created — gas.

"It''s amazing the amount of gas that''s produced by this bacteria, which is normal and bacteria that you want," Dr. Stone says. "It''s liters of gas, but you don''t end up expelling liters of gas. Most of it gets re-absorbed. The colon absorbs the carbon dioxide gas and other bacteria consume some of the hydrogen gas. Not all of it gets consumed, so you expel some of it. In tiny quantities there''s methane and sulfur gas, and that''s what makes it stink."

Because society has taught people to think that flatulence is gross or funny, some Americans may be too embarrassed to see a physician even though they live with the discomfort or bloating from excessive gas. Excessive gas could be a sign of Irritable Bowel Syndrome (IBS). Dr. Stone says more than 40 percent of Americans have some symptoms consistent with IBS.

In some patients with IBS, the amount of gas in the intestines will cause the symptoms. The problem isn''t the gas itself, the symptoms are the result of how the bowel senses and handles that gas.

"In the last few years, we''ve learned why patients with IBS complain about too much gas. IBS is a combination of hypersensitivity and abnormal motility of the small intestines," Dr. Stone says. "The intestines are hypersensitive to the air, fluid, food or anything that stretches the bowel. These two factors combine in varying degrees and severity to cause the classic symptoms of IBS — changes in bowel habits, abdominal distention, abdominal pain, and in some cases, the feeling of excessive intestinal gas or flatulence."

For someone who has IBS and doesn''t know it, eating something such as pizza may lead to discomfort.

"If you eat a lot of fat, it slows your digestion because it takes more energy and time to digest fat than non-fat," Dr. Stone says. "If you eat a fatty meal like a big pizza — a typical American diet — and you have IBS, you''re setting yourself up for a major problem. You''re already sensitive to begin with, and you''re eating a fatty meal that will slow down digestion even more, so the air you produce in your colon will be retained longer. You''ll feel bloated and your abdomen will distend — frequent complaints of patients who have irritable bowel."

In addition to fatty foods, other foods loaded with carbohydrates, such as beans, broccoli and leafy veggies, actually produce more gas.

"These foods have sugars that we can''t digest. Nobody can. We''re just not capable of doing it," Dr. Stone says. "Those excess carbohydrates end up in the colon and get broken down by bacteria, which produce gas as a byproduct. That''s why you get excessive gas after eating certain foods, and thus eating those foods may result in more problems especially if you have IBS."

For the remaining 60 percent of Americans who don''t have IBS or other gastrointestinal complications, Dr. Stone isn''t suggesting giving up beans for the protein or broccoli for vitamin C and calcium to minimize flatulence.

In short, eat a varied, balanced diet, and watch the amount of food you eat. And simply realize certain foods will cause flatulence.

"We have a society that eats too much," Dr. Stone says. "If you eat less of everything, then you''re going to have less gas produced."

Dr. Stone says some people go so far as prescribing beano® for themselves. "Products like beano have not been proven to be of benefit," Dr. Stone says. "When someone reports that it helps them, the benefit may simply be a placebo effect, rather than an actual reduction of gas produced."

The vast majority of people with occasional IBS symptoms don''t need to seek any medical care. If symptoms are severe enough to cause a disruption of daily activities, then a primary care physician or gastroenterologist should address them.

For a referral to a Washington University gastroenterologist, call 314-TOP-DOCS (314) 867-3627 or toll free 1-866-867-3627.

Written by Brian Bretsch, asst. editor BJC Today.