How much we fart in a day, according to science — and which age group is the gassiest

This study’s a stinker.

Researchers decided to find out how frequently we fart in a day, counting the gas passed by 6,400 people across Australia — and collecting data on all 360,192 of their toots.

Given how flatulence can give us insight into gut health, it’s surprising how little we know about the line between what’s good and what’s excessive, researchers say.

Gone with the wind

Scientists had to solve a problem: How do you count farts?

This year, researchers at the University of Maryland created Smart Underwear, a small device that snaps onto underwear and sensors track farts automatically.

There was also the option to insert something into the bum to measure gas getting built up. The problem there is people often hold it to release in a more socially acceptable place.

So, an Australian team came up with a solution: they call it “Chart Your Fart.”

They gave participants an smart phone app where they could log their toots as soon after it’s released as possible. The app was designed to be discrete so everyone around participants wouldn’t be clued in to their flatulence habits.

All sorts of people joined the study, from ages 14 and up. The only people who weren’t considered were those who recently made a major diet change, which could cause abnormal farting.

Who farts the most?

On average, people fart 5 times a day, the study showed. The median — meaning the middle number of a graph — was slightly lower (3.8 farts a day), which means there was a subset of very gassy people driving up the average.

This is true across demographics: men, women, young, old — a few folks passed gas significantly more than the rest in the group, making the average at least 1 higher a day than the median.

A vast majority (79.3%) recorded between 2 and 7 farts a day.

Men recorded more farts than women: 5.2 vs. 4.8 a day, on average. The youngest (age 14-25) recorded the least farts at 4.4 on average.

Ages 26-45 farted the most, with slightly more than 5 a day. But the next group, 46-65 was close at exactly 5 a day. Researchers said they didn’t get enough data from folks ages 65 up.

Researchers also found when farts happen during the day: they gradually increase until a peak in the evening after dinner. There are small spikes at 6-8 a.m., after lunch at 2-4 p.m., and the last big one from 8-10p.m.

This largely correlates with when people are taking in energy and fiber through food. Farts follow after an hour or so.

Why farts matter

This study shows average farts a day much lower than previous research. Some say 14 to 23, while the Smart Underwear device detected people farting from 4 to 59 times a day.

This is explained in part by the nature of the Australian study — you have to be awake to log your toots in the app, so it misses all nighttime flatulence.

Passing gas is a necessary part of the body’s normal functioning, but farting too much could be a sign something’s wrong. That’s why researchers emphasize a need for more baseline data on what “normal” farting habits look like.

For example, farting too much could be a sign you’re sensitive to a particular type of food, like milk (lactose) or gluten.

Other conditions, from diabetes to hypothyroidism, could cause excess gas. It could also be irritable bowel disease, or bacterial overgrowth in the small intestine.

Again, farting is normal, though habits can change farting. Smoking, chewing gum, and carbonated drinks introduce more air to the gut, producing more farts. High fiber foods like beans, lentils, broccoli, and brussel sprouts also cause gas by fermenting in the colon.