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Flatulence or gas can be annoying and embarrassing, but it is something that just about everyone has experienced to varying degrees. The good news is that you do not have to endure it. Well, at least not all the time.
What Causes Gas?
The first step toward lessening gas is learning what causes it. Most intestinal gas in healthy people results from bacterial fermentation in the colon. Complex carbohydrates are the cause of the rectal gas we pass. These include certain sugars, starch, and fiber.
A normal diet contains a lot of carbohydrates that aren't digested by enzymes in the small intestine. Instead, they are dumped into the colon. Carbohydrates end up in the colon everyday, where they're digested by bacteria. This fermentation by bacteria gives off gas.
The meanest gas-producing carbohydrates, raffinose and stachyose, are found in beans. These include kidney beans, lima beans, black beans, navy beans, and soybeans.
Lactose, which is found mostly in milk and dairy products, can also cause excess gas in some people. People who do not have enough of the enzyme lactase, which digests lactose, experience gas. This condition, known as lactose intolerance, is much more common among people of Asian, Native American, and African decent, than among people of European decent.
The sugars fructose and sorbitol are also gas producers of the carbohydrate clan. Fructose is found in many fruits and vegetables. Sorbitol is found in fruits, including apples, peaches, and pears. Sorbitol is also an artificial sweetener commonly used in sugar-free food products and candy.
Starches and Fiber
Aside from sugars, starch and fiber camp out in the colon too. Starches include potatoes, pasta, and rice. (Rice does not lead to gas, though.) Soluble fiber found in oat bran, beans, peas, and most fruits can also give off gas.
You probably knew that eating food causes gas, but what about eating air? Air swallowing is one of the most common causes of gas, and it can be caused by eating quickly and taking in large amounts of air.
Swallowed air primarily escapes through belching, not through the rectum, but some can still get all the way through.
Air swallowing can also be completely unrelated to eating. Other causes of swallowed air, according to gastroenterologists and dietitians, include the following:
What Makes Gas Smell?
Of all the gas we pass, researchers estimate that a very small amount is actually odor producing. Odorless gas consists of nitrogen, oxygen, hydrogen, methane, and carbon dioxide. Researchers suspect that odorous gas consists of sulfur compounds.
What Is a Normal Amount of Gas?
The average person passes gas 14 times a day. In fact, passing gas less than 25 times a day is considered normal.
How to Reduce Gas
Take these five steps towards reducing flatulence:
- Avoid gas-producing foods at inconvenient times—Do not cut them from your diet completely. Most gas-producing foods are very healthy.
- Introduce fiber slowly— Gradually introduce fruits, vegetables, and whole grains to your diet. You may want to start off eating one or two fruits and vegetables a day for a week. You should then up your fiber intake to five servings of fruits and vegetables a day over the next week or so. Remember to drink at least eight glasses of water a day to help prevent constipation.
- Try taking a digestive aid like Beano—Beano is an enzyme that is available over-the-counter. This digestive aid may be able to break down certain starches, reducing flatulence.
- Keep a food diary—Write down what you eat and how it affects you. You may be able to determine what is causing you to have excess gas, then modify your diet accordingly.
Should I See a Doctor For My Gas?
Call your doctor if you have:
- Worsening flatulence that bothers you, or that suddenly changes
- New flatulence, especially if you are over the age of 40
- Severe gas pains or other symptoms, such as weight loss associated with the flatulence
It may not be the easiest subject to talk about, but only your doctor can rule out serious health problems.
American Dietetic Association
American Gastroenterological Association
The Canadian Association of Gastroenterology
Dietitians of Canada
Gas in the digestive tract. American Gastroenterological Association website. Available at: http://www.gastro.org/patient-center/digestive-conditions/gas-in-the-digestive-tract. Accessed December 11, 2013.
Gas in the digestive tract. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: http://digestive.niddk.nih.gov/ddiseases/pubs/gas. Updated January 2, 2013. Accessed December 11, 2013.
Preventing gas and flatulence. Harvard Medical School website. Available at: http://www.health.harvard.edu/press%5Freleases/gas-flatulence. Published October 2007. Accessed December 11, 2013.
- Reviewer: Michael Woods, MD
- Review Date: 12/2013
- Update Date: 12/11/2013