Belching, bloating, flatulence, etc., are terms that are commonly used in association with gas buildup in the stomach and intestines. The term flatulence denotes expulsion of intestinal gas through the rectum. 'Flatus' is the term that refers to intestinal gas, the main constituents of which are nitrogen, carbon dioxide, and a small amount of hydrogen and methane. Apart from the discomfort caused by the condition, flatulence can also be embarrassing at times.

What Causes Excessive Gas?

Swallowed Air: It is quite normal to swallow a small amount of air while eating or drinking. Those with the habit of eating rapidly, gulping liquid, chewing gum, sucking hard candies, or smoking cigarettes, may ingest a large amount of air, which gets accumulated in the stomach. The air that we swallow usually consists of nitrogen and oxygen. While oxygen is absorbed by the lining of the gut, nitrogen is not absorbed in this manner, and so it can pass into the intestine and cause flatulence. A major portion of the air swallowed during eating or drinking is expelled through the mouth (as belching).

Intestinal Bacteria: Intestinal gases are byproducts that are generated when bacteria act on carbohydrates and fiber. Numerous bacteria are found in the human intestine and some of them even participate in the process of digestion, especially in digesting those foods that cannot be completely digested by the stomach enzymes. They include foods with complex carbohydrates and a high fiber content. The semi-digested or undigested food reaches the colon, where they are broken down by intestinal bacteria. In this process, gases like carbon dioxide, methane, and hydrogen are produced. Certain foods may release sulfur-containing gases, when they are broken down by bacteria. Such foods are responsible for smelly flatus.

Normal Digestion: Sometimes, gases like carbon dioxide can be produced even during normal digestion. This happens due to the interaction between stomach acids, bicarbonates in the bile, and pancreatic juices. Pancreatic juices are alkaline and they neutralize digestive acids; but this reaction produces carbon dioxide, which can cause flatulence.

Other Causes
  • There are certain medical conditions that affect digestion of foods, thereby causing flatulence. They include lactose intolerance, irritable bowel syndrome, constipation, etc. In case of lactose intolerance, milk and dairy products remain undigested, thereby allowing bacteria to ferment them and produce gas.
  • Consumption of foods like cabbage, beans, onions, potatoes, bread, cauliflower, broccoli, asparagus, dairy products, fatty foods, sprouts, etc., may cause flatulence. Being rich in starch or fiber, these foods cannot be fully digested by the digestive enzymes. Such foods remain semi-digested or undigested when they reach the colon, where they are broken down by bacteria break down these foods, and gases are produced as a byproduct.
  • Sometimes, use of laxatives like sorbitol, lactulose, etc., may cause flatulence.

Passing air through the rectum is the most common symptom of flatulence, which may also cause bloating, belching, abdominal pain and cramps, rumbling in the lower portion of the abdomen, and a burning sensation in the stomach. Sometimes, the flatus can be loud and smelly.


Mild flatulence is considered normal, and does not require any treatment. However, excessive flatulence can cause a lot of discomfort, for which medical intervention is needed. Generally, it can be cured by following some simple precautionary and preventive measures. Sometimes, simple dietary or lifestyle modifications are enough to prevent this condition.

Chew foods slowly and thoroughly, so as to prevent ingestion of air and to promote digestion of carbohydrates. Proper chewing helps to break down carbohydrates, which can be easily digested by stomach enzymes. Avoid those food items that cause bloating and flatulence. Those with lactose intolerance should avoid milk and dairy products to get rid of flatulence. Reduce intake of high-fiber foods. You may also try home remedies like baking soda mixed in water. Ginger provides relief from indigestion and flatulence. Fennel seeds, cinnamon, clove, cardamom seeds, cumin, and coriander, are also effective for this purpose. Activated charcoal tablets are commonly used for eliminating intestinal gas. However, consult your physician before taking charcoal tablets. Digestive enzyme supplements and probiotics may also help to reduce flatulence.

Generally, home remedies and over-the-counter medications, along with dietary changes and increased fluid intake are sufficient to provide relief from gas problems. As far as over-the-counter medications are concerned, take them under the guidance of your physician. If there is no relief, consult your physician to get the condition diagnosed and treated.

Disclaimer: This article is for informational purposes only, and should not be used as a replacement for expert medical advice. Visiting your physician is the safest way to diagnose and treat any health condition.