Gas in your digestive system is part of the normal process of digestion. Getting rid of excess gas, either by burping or passing gas (flatus), also is normal. Gas pain may occur if gas is trapped or not moving well through your digestive system.
An increase in gas or gas pain may result from eating foods that are more likely to produce gas. Often, relatively simple changes in eating habits can lessen bothersome gas.
Certain digestive system disorders, such as irritable bowel syndrome or celiac disease, may cause — in addition to other signs and symptoms — an increase in gas or gas pain.
Signs or symptoms of gas or gas pains include:
- Passing gas
- Pain, cramps or a knotted feeling in your abdomen
- A feeling of fullness or pressure in your abdomen (bloating)
- An observable increase in the size of your abdomen (distention)
Burping is normal, particularly during or right after a meal. Most people pass gas up to 20 times a day. Therefore, while having gas may be inconvenient or embarrassing, burping and passing gas are rarely by themselves a sign of a medical problem.
Excess upper intestinal gas can result from swallowing more than a usual amount of air, overeating, smoking or chewing gum. Excess lower intestinal gas can be caused by eating too much of certain foods, by the inability to fully digest certain foods or by a disruption in the bacteria normally found in the colon.
Foods that cause excess gas
Foods that cause gas in one person might not cause it in another. Common gas-producing foods and substances include:
- Beans and lentils
- Vegetables such as cabbage, broccoli, cauliflower, bok choy and brussels sprouts (cruciferous vegetables)
- Dairy products containing lactose
- Fructose, which is found in some fruits and used as a sweetener in soft drinks and other products
- Sorbitol, a sugar substitute found in some sugar-free candies, gums and artificial sweeteners
- Carbonated beverages, such as soda or beer
Digestive disorders that cause excess gas
Excessive intestinal gas — belching or flatulence more than 20 times a day — sometimes indicates a disorder such as:
- Autoimmune pancreatitis
- Celiac disease
- Crohn’s disease (a type of inflammatory bowel disease)
- Dumping syndrome
- Eating disorders
- Gastroesophageal reflux disease (GERD)
- Gastroparesis (a condition in which the muscles of the stomach wall don’t function properly, interfering with digestion)
- Inflammatory bowel disease (IBD)
- Intestinal obstruction
- Irritable bowel syndrome
- Lactose intolerance
- Peptic ulcer
- Ulcerative colitis
Intestinal gas definition and facts
- The intestine normally contains gas that is rapidly transmitted through the small intestine to the colon (large intestine). The amount of gas that is normally present is dependent on the effects of colonic bacteria on the undigested food that reaches the colon and the speed with which the gas passes through the intestines and is passed. In healthy individuals, most of the lower intestinal gas that is passed (flatus) is produced in the colon and is not transmitted from the upper intestines.
- The definition of excessive gas varies by individual, usually based on what they have considered normal in the past. Some individuals consider excessive gas to be excessive belching or excessive burping, others excessive passing of gas (flatulence), and still others as the sensation of fullness in the abdomen. Although everyone goes through periods of excessive gas, particularly flatulence, it is only when the symptoms become chronic that people become concerned.
- The most common normal cause of belching is excessive gas in the stomach that comes from swallowed air. However, discomfort in the abdomen for any reason also may lead to excessive belching. Therefore, belching does not always indicate the presence of excessive gas in the stomach. It is not difficult usually to differentiate between excessive gas in the stomach and other causes of excessive gas. If the problem is gas in the stomach, belching brings relief. If the cause is not gas in the stomach, belching does not bring relief. Although excessive belching may be a sign of excessive gas, it usually is not and is rather a sign of abdominal discomfort of many causes or a learned habit of swallowing and immediately regurgitating the air as a belch. Rarely, excessive belching is due to swallowed air during acute psychiatric issues associated with anxiety.
- Bloating is the subjective feeling that the abdomen feels more full than it should be, but does not necessarily mean that the abdomen is enlarged. Distention is the objective enlargement of the abdomen. Bloating is not the same as excessive gas.
Continuous distention of the abdomen usually is caused by fluid, tumors, enlarged organs, or fat within the abdomen.
Intermittent distention of the abdomen may be caused by excessive formation of intestinal gas, but also physical or functional obstruction of the intestines.
- Belching and flatulence (farting or passing gas) are virtually universal. People fart on average 20 times per day. The number that defines a “lot” of burping has not been determined.
- Flatulence results from the production of gas by bacteria within the intestines (usually the colon) when they digest dietary sugars and polysaccharides that reach the colon undigested.
- Increased gas is not caused by irritable bowel syndrome (IBS) or most parasitic or bacterial intestinal infections. It also is not caused by gastritis, gastric cancer, gallstones, cholecystitis, and pancreatitis or cystic fibrosis (unless there is maldigestion of food). It also should not be confused with indigestion, which has causes other than gas.
- Excessive production of gas and increased flatulence may occur because of 1) the greater ability of some bacteria to produce gas, 2) maldigestion or malabsorption of sugars and polysaccharides such as that seen in chronic pancreatitis with pancreatic insufficiency, and celiac disease, and 3) bacterial overgrowth of the small intestine.
- Abdominal pain is not a common symptom of people with excessive gas, although the discomfort of bloating may be described as pain. Cramps and severe pain suggest causes other than gas, for example, intestinal obstruction that also can lead to abdominal distention and discomfort.
- Remedies for truly excessive gas include changes in diet and suppression of intestinal bacteria that produce the gas. There is no evidence that digestive enzymes, activated charcoal, and simethicone (Gas-X, Mylanta, and others) relieve excessive gas.
- The remedy for excessive belching not due to excessive gas is to develop new physical habits such as breathing with the mouth open.
- Foul-smelling gas (flatus) is not synonymous with excessive gas. The foul smell of flatus results from the types of food that are eaten and the types of gasses produced by the bacteria in the colon, particularly gasses that contain sulfur.
When to see a doctor
By itself, intestinal gas rarely indicates a serious condition. It can cause discomfort and embarrassment, but it’s usually just a sign of a normally functioning digestive system. If you’re bothered by intestinal gas, try changing your diet.
However, see your doctor if your gas is persistent or severe, or if it’s associated with vomiting, diarrhea, constipation, unintentional weight loss, blood in the stool or heartburn.