Causes of Intestinal Gas and What You Can Do About It

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Do you know what causes intestinal gas? Simply put, gassiness is a natural part of human digestion and only becomes a problem when it makes itself known at the wrong time. Learn why you have intestinal gas and what you can do if you believe your body is producing too much of it.

How Much Gas Is Too Much?

If you pass gas between 13 and 21 times a day, you are within the normal range, but it seems a little silly to count how often you fart. What's more important is your relationship with your own body. If you believe your body is gassier than it should be, then you may want to make some changes to reduce your gas level. Just keep in mind that the formation of intestinal gas is a good thing for the health of both your gut and immune system. So while you might choose to completely avoid gassy foods for an important occasion, this is not something you want to do altogether.


You may be reassured to know that there are only two primary causes of intestinal gas—swallowed air and the bacterial breakdown of substances found in certain kinds of foods. The following information should help you pinpoint what might be causing the problem for you.

Swallowed Air

In the normal course of the day, we all swallow some air. This air is generally released through the process of burping or belching. However, this air can also make its way to the large intestine where it is released through the rectum as flatulence.

There are things that can cause a person to swallow more air than normal. If any of the following apply to you, you now have something to work on:

  • Eating or drinking too quickly
  • Drinking carbonated beverages
  • Gum chewing
  • Smoking: cigarettes, cigars, and pipes
  • Sucking on hard candies
  • Poorly fitted dentures

Bacterial Breakdown

Some substances in the food that we eat are not well digested and absorbed by our bodies. When these substances, mainly carbohydrates like simple sugars and starches, arrive in our large intestines, they are acted upon by bacteria within our guts. The result of this breakdown is the release of gas. This gas is usually carbon dioxide, hydrogen, methane, and nitrogen. Although some of these gasses may be absorbed into the bloodstream and exhaled out, most of them are released through your anus.

The primary food components that can trigger the release of intestinal gas are:

  • Fructose: This sugar is found in some fruits and vegetables as well as in many processed foods in the form of high fructose corn syrup. It is estimated that approximately one-third of the population has difficulty digesting and absorbing fructose, a condition called fructose malabsorption. However, eating too many fructose-containing foods in close proximity of one another can result in excessive intestinal gas even in people who do not have fructose malabsorption.
  • Lactose: This sugar is found in milk and other dairy products. People who have lactose intolerance lack sufficient amounts of the enzyme lactase and thus are unable to digest lactose. When lactose is undigested, it becomes available to be acted upon by gut bacteria, with a subsequent release of gas.
  • Raffinose: The high amount of this sugar in beans contributes to their well-earned gassy reputation. Raffinose is also found in vegetables such as cabbage and Brussels sprouts.
  • Sorbitol: Sorbitol is naturally found in many fruits and is an artificial ingredient in many sugar-free food items. Sorbitol is classified as a polyol or sugar alcohol. Approximately half of the population are unable to absorb polyols.

What to Do for Intestinal Gas

Now that you have a sense of what might be causing you to experience excessive intestinal gas, you can take some steps to address the problem:

Don't delay your bowel movements. Are you one of those people who ignore the sensations to have a bowel movement until you get home? This might result in gas building up within the intestines, causing pain and bloating. And when you do pass gas, it may be smellier as it is moving around the stool. 

Watch what you eat when you really need to be gas-free. As we said before, intestinal gas is good for us. But for the days when it is extra important that you not be gassy, you can choose foods that are less likely to give you gas, and avoid those that have a reputation for being gassy. 

Look into a supplement. There are many over-the-counter supplements to choose from. Ask your pharmacist to guide you to the right one for you. Here are some options:

  • Probiotics
  • Lactase Supplements
  • Beano
  • Simethicone Products

Rule out an intolerance. If you suspect that you may have lactose intolerance, fructose malabsorption, or a problem digesting sorbitol, you can try eliminating foods that contain these carbohydrates from your diet for a short period of time to assess the effects on your system. To keep things simple and to avoid unnecessary restriction, you should pick one class of foods at a time for elimination. You should know within two weeks if the restriction helped. It is also useful to "challenge" yourself with the restricted food to see if symptoms return. And once you have identified a trigger food for you, you can experiment with smaller amounts to see how much of the food you can tolerate without experiencing unpleasant amounts of gas.

Talk to your doctor. If you suspect that your gas problem is really not normal, talk to your doctor about it. Your doctor can assess if there is some intestinal disorder that might be contributing to the problem. Excessive intestinal gas is typically not an indicator of a serious health condition, but it may be a symptom of either irritable bowel syndrome (IBS) or small intestinal bacterial overgrowth. Obtaining an accurate diagnosis opens up potential treatment options, including the use of prescription medication to reduce your gas. If you have IBS, you may find that following the low-FODMAP diet can also significantly reduce unwanted gas.

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Article Sources

  • "Gas in the Digestive Tract" National Digestive Diseases Information Clearinghouse (NDDIC)

  • Azpiroz, F. & Serra, J. "Treatment of Excessive Intestinal Gas" Current Treatment Options in Gastroenterology 2004 7:299-305.