On average, a person releases about 0.5 to 1.5 liters of gas per day. Most flatulence is odorless, but people rarely take the risk of farting in public, especially during important events or occasions.

So, how does holding in a fart affect our bodies?

Gas is a natural byproduct of digestion, and holding it in can cause discomfort, bloating, and even nausea.

From the moment you take a bite of food, your body begins to break it down mechanically and chemically. For example, your teeth mechanically crush the food, while your saliva chemically breaks it down. As food moves down the digestive tract, it is further broken down in the stomach, small intestine, and large intestine. The bacteria in the intestines help break food down into its most basic building blocks. These building blocks can then be absorbed into the bloodstream and transported throughout the body as energy.

However, not everything in food can be used by the body, especially if the body cannot fully break down certain substances. For instance, people who are lactose intolerant do not produce enough of the enzyme lactase in their small intestine, so lactose, a sugar in dairy products, remains and ferments in the digestive system, causing symptoms like bloating, diarrhea, and excessive gas.

However, gas accumulates even during normal digestion. According to the American Society for Microbiology, hydrogen sulfide (which can cause a rotten egg smell in flatulence) is produced by beneficial bacteria in the intestines breaking down proteins. Further down the digestive tract, carbohydrates are broken down in the large intestine, and their byproducts—hydrogen and methane—are added to the gas accumulating in the body. Even oxygen and carbon dioxide can be present in the intestines, absorbed when a person swallows food.

The external anal sphincter is the only part of the digestive process that we can consciously control. So, if we decide that it’s an inappropriate time to fart, we tighten the sphincter, and the gas is held in. With no way out, the gas is reabsorbed into the colon. Therefore, the farts suppressed during the day are often released during breaks or when the body relaxes in sleep at night.

Rather than holding it in, when you feel gas accumulating and ready to be released, you should proactively find a convenient place to let it out. Releasing gas naturally is the best way for your digestive system to function.