Why Do We Fart? Doctors Explain Gas, Causes & When to Worry

Nearly everyone experiences flatulence – the passing of gas – at some point, whether during a post-meal walk or even while sleeping. It’s a normal bodily function, but what causes it, and when should you be concerned?

According to Dr. Satish Rao, a professor at the Georgia Medical Faculty of Augusta University, the average person passes gas between seven and 24 times a day. This gas is a byproduct of fermentation in the large intestine. This process creates a mixture of gases including nitrogen, oxygen, methane, hydrogen, and carbon dioxide. Remarkably, 99% of the gas produced in the body is odorless; the unpleasant smells are due to sulfur compounds.

Dr. Rao explains that once gas is produced, there are two primary ways it can be expelled: “Some gases pass from the inner surface of the large intestine into the bloodstream and are exhaled. However, the other route is through flatulence. Gas needs to exit the body, and if it’s produced rapidly, it won’t be absorbed and will automatically exit through the anus.”

Some People Are More ‘Productive’

Dr. Folasade P. May, an associate professor at the David Geffen School of Medicine at UCLA, notes that some individuals naturally produce more gas. “People who chew a lot of gum, drink carbonated beverages, or eat very quickly may swallow more air, leading to bloating. Some individuals also have gut bacteria that produce more gas. Diet, digestive speed, and medications can all influence how often you pass gas.”

Foods That Can Increase Flatulence

Dr. Ed Giles from Monash University explains that foods causing gas are often those that are “fermentable.” These foods have a higher potential to produce gas in the gut. “They feed the bacteria in the gut, which then produce gases, including smelly ones like methane.”

Dr. Giles identifies some of the most gas-producing foods as:

• Beans
• Lentils
• Onions
• Garlic
• Broccoli
• Cabbage
• Cruciferous vegetables (like turnips)
• Certain grains and fruits
• Dairy products (if lactose intolerant)

When to Be Concerned

It’s important to pay attention to changes in your gas patterns. Consider be concerned if you begin experiencing painful or significantly different gas than usual. Consulting a doctor is advisable if you pass gas more than 23 times a day and it’s causing you problems.

However, it’s important to remember that some people naturally pass more gas than others, and this is often normal for them. Dr. May emphasizes, “The most important thing is whether there is pain, diarrhea, or blood with the gas. In these cases, it’s important to get evaluated.”

The composition of gut bacteria and individual digestive processes play a significant role in gas production. While dietary adjustments can often help manage excessive flatulence, persistent or concerning symptoms warrant medical attention to rule out underlying digestive issues.