The short answer: Does farting burn calories?
No meaningful calorie burn has been established for farting, and flatulence should not be used as a weight-loss method. The often-repeated claim that one fart burns 67 calories is not supported by the available physiology evidence.
A small study of five healthy men examined what happened during flatus-related events. It recorded propagated contractions in the colon, increased pressure in the rectum, and early relaxation of the anal sphincter. The study measured motor activity, not energy expenditure. As a result, it cannot provide a validated calories-per-fart estimate.
: an event can involve movement inside the body without producing a measurable or meaningful calorie expenditure comparable to physical activity. There is also no established alternative number that can reliably replace the unsupported 67-calorie claim. Loudness, odor, force, or frequency does not establish a higher calorie cost.
Passing gas may relieve pressure or bloating, but that is different from losing body fat. Farting is a normal digestive function, not a practical way to create a calorie deficit.
What happens in the body when you fart
Flatulence is intestinal gas leaving the body through the anus. Belching is different: it releases gas through the mouth.
Gas normally enters the digestive tract in two main ways. Some is swallowed air. More gas can form when bacteria in the large intestine break down carbohydrates that were not completely digested earlier in the digestive process.
Before gas passes, the colon and rectum undergo coordinated motor events. In the small physiology study described above, researchers observed propagated colonic contractions, increased rectal pressure, and early relaxation of the anal sphincter. These changes help move gas toward and through the anus.
The presence of contractions and pressure does not show that farting functions like exercise. Digestive organs can move and coordinate their activity without evidence of a meaningful calorie expenditure. Because the study did not measure energy use, it cannot support a specific calorie-per-fart figure.
Why farting can make you feel lighter without causing fat loss
Passing gas can reduce the sensation of pressure or fullness in the abdomen. That relief may make you feel physically lighter, but it does not mean that body fat has been lost or that a meaningful calorie deficit has occurred.
Bloating refers to a feeling of fullness or swelling in the abdomen. Distention means that the abdomen has become larger than usual. These experiences can occur together, but they do not always do so; only about half of people who report bloating also have distention.
When gas leaves the digestive tract, the amount of gas and pressure in that part of the gut may change. The resulting comfort is symptom relief, not evidence that fat tissue has been burned. Passing gas also does not provide a reliable measure of changes in body weight or waist size.
The temporary nature of this relief helps explain why farting can be mistaken for weight loss. A change in how the abdomen feels is not the same as a change in body composition.
Farting Calories: Myth or Fact
What causes frequent gas
Intestinal gas mainly comes from two pathways: swallowed air and bacterial breakdown of incompletely digested carbohydrates in the large intestine.
People may swallow more air when they chew gum, drink carbonated beverages, eat or drink quickly, or smoke. Some of that air can later leave through the anus rather than through the mouth.
The other major source is digestion by bacteria in the large intestine. Sugars, starches, and fiber that are not completely digested can reach the colon, where bacteria break them down and produce gas. Food effects vary from person to person, so a food that causes symptoms for one individual may not cause them for another.
Gas patterns can also occur alongside carbohydrate intolerance, constipation, irritable bowel syndrome, or other digestive conditions. Frequent farting alone does not diagnose any of these problems. The broader pattern matters, including whether symptoms are new, persistent, uncomfortable, or associated with changes in bowel habits.
When gas symptoms warrant medical advice
Passing gas is a normal part of digestion, and frequency varies among individuals. Studies summarized by the National Institute of Diabetes and Digestive and Kidney Diseases suggest an average of 8 to 14 anal gas passages per day, while experts consider up to 25 per day within a normal range. These population-level figures should not be used as a personal diagnostic cutoff.
Discuss gas symptoms with a doctor when they are bothersome, change suddenly, or occur with other symptoms. Relevant accompanying symptoms include abdominal pain, constipation, diarrhea, or unintentional weight loss.
The goal is not to treat a number of daily gas passages in isolation. A change from your usual pattern or a combination of digestive symptoms may provide more useful context than frequency alone. A healthcare professional can help determine whether the symptoms need further attention.
Frequently Asked Questions
Does a loud or smelly fart burn more calories?
No. Sound, odor, and force do not provide a validated measurement of calorie expenditure. There is no evidence that a louder, smellier, or more forceful fart burns more calories.
Does passing gas reduce body fat?
No. Passing gas may relieve bloating or abdominal pressure, but that is not the same as losing body fat. Feeling less full after gas passes does not prove that calories were meaningfully burned.
Is farting every day normal?
Daily farting can be normal because gas production and passage are part of digestion. Frequency varies, and population-level averages should not be treated as a diagnostic threshold for one person. Medical advice is appropriate if gas becomes bothersome, changes suddenly, or occurs with abdominal pain, constipation, diarrhea, or unintentional weight loss.
Is pooping the same calorie-burning question?
No. Defecation and flatulence are separate bodily events. This article does not provide a calories-per-bowel-movement estimate, and no unsupported number should be used for that question.