What Is Intestinal Gas?

Gas is a side effect of a normal, working intestinal tract

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Gas in the digestive system is either air (from the outside environment) or gases produced by bacteria inside the body. It's completely normal, although many people are embarrassed by belching (gas that escapes through the mouth) or flatulence (gas expelled through the rectum).

Gas can be upsetting and embarrassing, but it is a part of the digestive process, like it or not. Most people have a certain amount of control over how much gas is produced through altering diet, but there's always going to be some gas.

It's a good thing, actually, it means your digestive system is doing what it is supposed to do: break down foods into the vitamins and minerals that the body needs. 

What Gas Really Is 

The main components of gas include carbon dioxide, oxygen, nitrogen, and hydrogen. These gases do not give off an odor. However, gas that comes from the rectum may also include sulfur-containing compounds, which does have an unpleasant and distinctive scent.

Some people also have methane in their flatulence, which is produced in the large intestine during digestion. Methane production is not typical; only about a third of people have it in their flatulence. 

Gas in the Stomach

Gas that is found in the stomach can come from swallowing air (called aerophagia). Some air is naturally swallowed during talking and eating, but gulping drinks, chewing gum, or smoking can cause even more air to enter into the esophagus and potentially go down into the stomach.

Much of this gas is released the way it came in—through the mouth—as belching, but some does travel through to the stomach and beyond. Most of this gas is absorbed on its way through the intestines, but some may become flatulence and leave the body through the rectum.

Gas in the Intestines

Flatulence is a byproduct of food that does not get broken down completely in the small intestine.

Enzymes and bacteria that do the work of digesting food are present in the digestive tract. Some foods cannot be broken down fully by the enzymes in the small intestine, and are therefore passed into the large intestine. The large intestine contains a number of different forms of bacteria that continue the digestive process, but this process creates byproducts—carbon dioxide, hydrogen, and sometimes methane. These gases need to leave the body and do so by passing through the rectum as flatulence.

Pain or Discomfort From Gas

Some people may have gas in the digestive tract that causes them discomfort, such as abdominal bloating or distention. This can lead to a desire to make changes to the diet or lifestyle in order to have less gas. Keep in mind that everyone has gas and must therefore pass it several times a day. People who feel that they have an excessive amount of gas or that it is causing a disproportionate amount of pain, these concerns should be relayed to a physician.

A Word From Verywell

The body needs to produce gas during the process of breaking down foods for use by the body. This is an important process, even if it can be troublesome at times. While there's nothing that can be done about the body's need to produce gas, eating to reduce the amount of gas you have can help with symptoms of bloating and distention.

Most people don't actually have too much gas, even though it can seem that way at times. Making some changes in diet and lifestyle can often help, but if bloating is still out of control, consulting a doctor is a good choice.

Source:

Clearfield HR. "Intestinal Gas Problems." American College of Gastroenterology 2011. 2 Aug 2013. [PDF]

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