Why do we fart?

Flatulence, also known as a fart, is something everyone experiences. It’s the release of intestinal gas, which forms as a result of digesting food. Gas can be found throughout the digestive tract, including the stomach, small intestine, colon, and rectum.

We fart because of the buildup of gas in our bodies, typically due to:

  • Swallowed air: We swallow air throughout the day, including from carbonated beverages or taking in air as we chew.
  • An overgrowth of bacteria in the small intestine: Several conditions can lead to bacteria overgrowth, including type 2 diabetes, celiac disease, liver disease, and inflammatory bowel disease.
  • Carbohydrates that haven’t been fully digested: Sometimes all your food doesn’t get fully digested by the enzymes in the small intestines. When partially digested carbs reach the colon, bacteria convert part of that food into hydrogen and carbon dioxide gasses.

All that gas has to go somewhere. Some of it can be absorbed by the body. But when too much of it gathers in the upper part of your colon and puts pressure on the colon wall, you can feel pain in your abdomen or even all the way up into your chest. Flatulence, though, allows for a painless means of escape for this gas.

Sometimes you may experience more flatulence than usual. Increased farting can stem from a natural body reaction, or in some cases, an underlying medical condition. Factors that can affect how much you fart include:

Time of day

A buildup of gas-producing foods and swallowed air during the day may make you more flatulent in the evening. Also, you’re more likely to fart when the muscles in the intestines are stimulated. When you’re about to have a bowel movement, for example, those muscles are moving stool to the rectum. But other activities can also trigger flatulence, such as exercise or even coughing.

Certain foods

Foods ranging from beans to broccoli to bran can make some people gassier. Foods don’t affect everyone the same way, though. You may know your troublesome foods, so be aware of them if you’re concerned about being gassy. You may also be among the many people who lack the enzyme lactase, which is essential for properly digesting dairy products. You can be born with this lactose intolerance or it could develop as you age.


Alongside the amazing changes your body goes through when you’re pregnant, there are some unpleasant changes, such as increased gas production. This change is the result of increased hormonal activity that tends to slow down your digestion, allowing more gas to build up in your intestines.


Hormonal changes during your period can also coincide with bacteria changes in your digestive tract that can sometimes lead to increased flatulence.

Medical conditions

Diseases of the digestive tract may cause you to produce more gas. Surgery that affects the intestines could result in bacterial overgrowth there, and the subsequent production of more intestinal gas.

Preventing increased gas may be as simple as adjusting your diet. If you’re lactose intolerant, your doctor will advise you to avoid milk-based products. Using a lactase supplement that provides the enzyme to make digesting dairy easier may also be an option.

To decrease your gas, you may want to stop drinking carbonated beverages.

If you’re especially sensitive to beans or other common culprits, eating smaller portions or swapping them out for other healthy foods may be options for you. Be careful not to suddenly boost your fiber intake, as that can also cause gas problems.

The average person farts about 15 times per day, though you may pass gas much more or less frequently. You may be unaware of much of this activity because you’re asleep or the gas release is so minor.

But if you experience excessive flatulence, you should see a doctor. It could mean you have a gastrointestinal problem. You definitely shouldn’t hesitate if you also experience painful cramps, bloating or other symptoms. Conditions such as irritable bowel syndrome, Crohn’s disease, celiac disease, lactose intolerance, and peptic ulcers are all associated with excessive gas other unpleasant symptoms.