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Peninsula Gastroenterology Medical Group, Gastroenterologists
Redwood City: 2900 Whipple Ave | Suite 245 |Redwood City, CA 94062 • Phone: 650-365-3700
Mountain View: 2495 Hospital Drive | Suite 600 | Mountain View, CA 94040 • Phone: 650-964-3636

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What is Gas?

Everyone complains of excessive digestive gas at one time or another. Although gas can be uncomfortable and inconvenient, it is rarely anything to be concerned about. Gas is most often the result of certain habits or dietary choices. It can occur in one of two ways, either by excessive quantities of swallowed air or it is produced in the digestive tract.


Everyone will occasionally belch, especially after eating. However, some people belch frequently. Belching is the result of too much air in the stomach. The more a person swallows, the more air goes into the stomach and the more belching they will experience. Belching can usually be reduced by making some simple lifestyle changes:

  1. Air swallowers should concentrate on swallowing less.
  2. Avoid chewing gum and sucking on hard candies, using straws and drinking through bottles with small mouths. Avoid smoking and Ill-fitting dentures.
  3. Avoid carbonated beverages and fizzy medications.
  4. Eat more slowly.


Bloating, or the sense of swelling in the abdomen, is not necessarily caused by too much gas. Usually bloating is caused by poor motility, or slow movement of the intestinal tract. Bloating is often a symptom of irritable bowel syndrome, a condition of excessive bowel spasm. Eating fatty foods can also slow motility. In rare cases bloating can be a symptom of a more serious disease. For this reason your doctor may order additional tests such as x-rays or an endoscopy. Your doctor may prescribe medications to stimulate the motility of the intestinal tract.

Rectal Gas

Excessive rectal gas is most often produced by the bacteria in the colon. There are hundreds of different bacteria in the colon; most are harmless, and in fact, helpful to digestion. In the process breaking down nutrients, the bacteria generate a variety of gases. Normally many of these gases are reabsorbed and do not cause excessive flatulence. Some people have disorders that interfere with the digestion of certain foods, such as lactose. Some foods contribute to excess gas, such as beans, cruciferous vegetables and bran. For people that are bothered by excessive gas it may help to try an elimination diet. Experiment with eliminating certain foods for a few days, and then reintroducing them slowly, while observing for increasing symptoms. Some of the foods to eliminate include: legumes, milk products, cruciferous vegetables, root vegetables, some fruits (prunes, raisins, apples, bananas), wheat products, fatty foods and carbonated beverages.

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While you are a patient at Atherton Endoscopy Center, our highly competent and professional staff will care for you. Everyone from the receptionist to the physician embraces our philosophy of patient-focused care. Above all, our staff is friendly and concerned for your comfort.