The buildup and release—through burping or farting, to put it bluntly—of gas is a normal and universal bodily process. 

Although it’s natural, there’s a bit of a social stigma to it, which can mean we don’t talk about it much—at least, not in an informative way.

We spoke to Rosario Ligresti, M.D., chief of gastroenterology and director of The Pancreas Center at Hackensack University Medical Center, to get the 411 on flatulence.

Is it dangerous to hold gas in?

We’ve all been in situations where we really needed to let loose but could not. Is this harmful? The pressure is uncomfortable and distracting at best—and downright painful at worst. Are you going to rupture something if you hold in a fart?

The good news is that, no, you won’t harm yourself if you need to keep it in.

“Gas that is not passed will be absorbed by the bloodstream and ultimately breathed out by the lungs,” says Dr. Ligresti. “Holding gas in can be uncomfortable due to intestinal distension, leading to bloating or nausea. However, it ultimately is not harmful—but also not recommended.”

In other words, it’s always better out than in. Spare yourself the discomfort; it’s a perfectly normal and natural process. 

Gas Facts 101

People pass between 500 and 1500 mL of gas daily. Men pass gas on average about 13 times per day, while women pass gas about seven times. 

“The gas passed per rectum is 99 percent odorless, and swallowed air is responsible for most of the gas in the intestines,” Dr. Ligresti says. “Its composition is in fact much like the air: nitrogen, oxygen, and carbon dioxide.“

Hydrogen and methane account for the remainder of the gas produced, and these come from bacterial fermentation of poorly or non-digestible sugars in the colon. 

The odiferous gasses are present in very low concentrations in flatulence: 

• Hydrogen sulfide (a rotten egg smell)
• Methanethiol (rotten cabbage)
• Garlic-like dimethyl sulfide

These too are made by colonic bacteria and what they are digesting. 

At even lower concentrations, three other compounds can be found in gas that also smell bad: indole, skatole and rarer sulfur compounds. These compounds vary in concentration, depending on your diet or the bacteria in your digestive system, Dr. Ligresti says. 

People who are lactose intolerant produce higher quantities of hydrogen and methane. This is because if people lack the enzyme to digest lactose, this sugar is then available for gut bacteria to consume (and produce gas). When you eat lots of legumes that are poorly digestible (like cabbage, kale or beans), the gut bacteria also have lots of food to digest and produce more gas.

When to See a Doctor for Your Gas 

If you feel that you or a family member produce excessive amounts of gas, or you are concerned about unhealthy odors, it could be a good time to talk to your doctor, Dr. Ligresti says. 

“If there is a concern, we often look for issues related to gut motility, such as lactose intolerance, bacterial overgrowth, scleroderma (an autoimmune disease) and other uncommon causes,” explains Dr. Ligresti. “If the main symptoms are abdomen pain or bloating, lots of other potentially serious diagnoses may be present, and it’s best to see your gastroenterologist.”

Next Steps & Resources:

• Meet our source: Rosario Ligresti, M.D.
• To make an appointment with a gastroenterologist near you, call 800-822-8905 or visit our website.
• Learn more about gastroenterology at Hackensack Meridian Health

The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.