Gas and Bloating

The passing of gas is a normal bodily function.
Some people experience excessive gas which may make them feel uncomfortable.
Gas is caused by swallowed air and the food we eat.
People can often control their gassiness through diet.

How to Reduce Gas in the Digestive Tract

The following suggestions may be helpful to reduce gas:

  • Avoid chewing gum or sucking on hard candies (especially sugarless gum or sugar free candies that contain sorbitol).
  • Increase the amount of fluid you drink, but eliminate carbonated drinks and alcoholic beverages and reduce foods containing high-fructose corn syrup from your diet.
  • If you have lactose intolerance, avoid milk and milk products, such as soft cheeses, or try milk in which the lactose is already broken down.
  • Eat less gas-producing foods such as cauliflower, brussel sprouts, bran, beans, broccoli and cabbage. When eating such foods, you may consider trying over-the-counter gas relief medicines (Beano), which may help breakdown the non-absorbable carbohydrates found in these foods.
  • Walking, jogging, calisthenics and other exercise help to stimulate the passage of gas through the digestive tract.
  • Do not smoke or use other tobacco products
  • If you wear denture, check with a dentist to make sure the dentures fit properly.
  • Keep calm. Tension and anxiety can lead to more air swallowing.


All of us have gas and must get rid of it in some way. Normally, gas passes out through the rectum or is belched through the mouth. These are both necessary functions of the body that allow us to eliminate gas.

When gas does not pass out of the body easily, it can collect in some part of the digestive tract, causing bloating and discomfort. Even normal amounts of gas in the body can bother people who are sensitive to this pressure. Although gas is usually not a sign of a medical problem, it can be.

The amount of gas that people produce varies. Most people produce between a pint and a half-gallon of gas each day. Oxygen, carbon dioxide and nitrogen from swallowed air make up a large part of flatus (gas). Fermenting foods in the colon produce hydrogen and methane as well as carbon dioxide and oxygen. All of these components of flatus are odorless. The unpleasant odor of some flatus is the result of trace gases, such as hydrogen sulfide, which are produced when foods decompose in the colon.

Causes of Gas & Belching

A common source of upper-intestinal gas is swallowed air. Each time we swallow, small amounts of air enter the stomach. This gas in the stomach is usually passed into the small intestine where part of it is absorbed. The rest travels into the colon (large intestine) to be passed out through the rectum.
Gas can be belched out instead of being passed from the stomach into the intestine. This happens for several reasons:

  • Beverages contain carbon dioxide, which can produce large amounts of gas when warmed in the stomach. People under a lot of stress often swallow large amounts of air.
  • Some people swallow air frequently because they have post-nasal drip, chew gum or smoke.
  • Rapid eating or poorly fitting dentures also may cause too much air to be swallowed.
  • Drinking beverages that contain carbonated water may increase gas in the digestive tract. Try to avoid carbonated or “sparkling” drinks.
  • Some people have a sluggish bowel that does not get rid of air readily. Others might have an irritable bowel or spastic colon, which means that they cannot tolerate gas accumulation inside of the intestines, so even small amounts of air feel uncomfortable.

Repetitive Belching

Some people experience frequent belching. This might occur after a person has swallowed air without realizing it. Sometimes belching accompanies the movement of stomach material back up (reflux) into the esophagus. To clear material from the esophagus, a person may swallow frequently, which leads to more intakes of air and further belching.

Another cause of repeated belching is gastritis (inflammation of the stomach lining). There are many causes of acute or chronic gastritis, but the most common cause is infection with a bacterium called Helicobacter pylori (H. pylori). This bacteria can be detected with a breath test, stool test, blood test or from a biopsy from the stomach obtained during an upper endoscopy.

Foods & Gas

The foods we eat can be a factor in the production of gas in the lower intestine. These foods include:

  • Cauliflower
  • Brussels sprouts
  • Dried beans
  • Broccoli
  • Cabbage
  • Bran
  • Fiber

Today, many people are trying to improve their nutrition and health by eating more fiber. However, some people discover that adding large amounts of fiber to their diets causes gassiness. This can happen when someone begins eating more whole-grain cereals, such as whole bran, oatmeal or oat bran, more whole-grain breads or more fresh fruits and vegetables. They get a feeling of being bloated when they first begin the high-fiber diet, but within three weeks or so, they may adapt to it. Some people, however, don’t adapt, and the bloating from eating a lot of fiber can be a permanent problem.

Milk & Dairy

A common cause of excess lower-intestinal gas is that a person’s body may not have enough lactase, an enzyme normally found in the small intestine. Lactase is needed to digest lactose, the sugar found in milk and other dairy products. When this sugar passes undigested into the colon, it is fermented by bacteria, and gas forms. This can be a cause of excessive flatulence.

If lactase deficiency is suspected of causing your gas, you can stop eating dairy products for a while to see if you have less gas. If you find milk causes gassiness, you may consider drinking milk in which the lactose has been broken down (Lactaid milk). You can also take lactase enzymes (Lactaid) with each bite or drink of dairy products for a week to see if your symptoms improve. Lastly, a breath test is available to find out if you are lactose intolerant.

Fruit & Sweeteners

Finally, ingestion of large quantities of foods that contain fructose, a sugar commonly found in fruits and processed foods in the form of high-fructose corn syrup, may also contribute to gassiness. The small intestine can only absorb a limited amount of fructose each day. As with undigested lactose, it passes into the colon where it is fermented by bacteria. Artificial sweeteners, such as sorbitol, found in diet food products are also poorly absorbed and a source of excessive gassiness.

Abdominal Pain & Bloating

Eating a lot of fatty food can cause bloating and discomfort because the fat delays stomach emptying, allowing gas to build up there. This problem can be avoided by eating less fatty meals.

Gas, in the upper abdomen, is often reduced by belching. Gas can collect anywhere in the lower intestine. It often collects in the left side of the colon, and when severe, the pain can be confused with heart disease. When gas collects in the right side of the colon, the pain can be confused with gallbladder disease or even appendicitis.

A bloated feeling is probably not anything to be concerned about, but it can be a symptom of a more serious problem. If your problem is chronic, or if you are experiencing a severe increase in gassiness, you should talk to your doctor.

  • Additional Treatment Options
  • Activated charcoal may decrease odor from gas.
  • Miralax and other stool softeners may help people who are also constipated.
  • Simethicone (Gas-X) and digestive enzymes, such as the lactase enzymes.
  • Amitiza a prescriptio medication that increases fluid secretion and motility in the intestines
  • Supplements that break down the non-absorbable carbohydrates responsible for gas caused by beans and some vegetables, such beano, may be helpful.