Flatulence is a buildup of gas in the digestive system that can lead to abdominal discomfort.

Excessive flatulence can cause discomfort and distress. It often occurs due to eating certain foods, but it can be a sign of a more serious condition. Most people experience flatulence at one time or another.

In most cases, a change of diet and lifestyle can help control excessive gas.

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There are two causes of gas buildup in the digestive system. Firstly, when we eat, drink or swallow saliva, we also swallow tiny amounts of air. This swallowed air accumulates in the gut.

Secondly, when we digest food, bacteria create gas, mainly hydrogen, methane, and carbon dioxide. When food decomposes in the digestive system, it can also produce sulfur, which can produce an odor on expulsion.

As the gas builds up, the body may need to eliminate it through the mouth, by belching, or passing wind through the anal passage.

Flatulence often occurs without the person being aware of it. The average person expels gas through the anus 8-14 times per day.

Flatulence can result from normal bodily processes, or it may stem from a condition affecting the digestive system.

Exogenous sources are those that come from outside. We swallow air when we eat, drink, or swallow saliva, especially when the body produces excess saliva due to nausea or acid reflux.

Endogenous sources are inside the gut. Gas may arise as a by-product of the partial digestion of certain foods.

Why do some foods cause more gas?

Certain foods contain sugars, starches, and fibers that the body cannot fully digest. When these items pass to the large intestine, bacteria begin to break them down, creating gas.

Foods that cause flatulence tend to be those high in certain polysaccharides, particularly oligosaccharides, such as inulin. Inulin belongs to a class of dietary fibers known as fructans.

Examples of foods that can worsen flatulence include:

Here are some reasons why some foods cause more gas, but there are others.

  • Complex carbohydrates: Complex carbohydrates in beans are difficult for humans to digest. When the complex carbohydrates reach the lower intestine, bacteria feed on them and produce gas.
  • Lactose intolerance: When people consume food that contains lactose, such as milk, and lack the enzymes to break it down, the bacteria feed on the lactose. In people with lactose intolerance, this produces large amounts of gas.
  • Celiac disease: Intolerance to the protein gluten means that people with celiac disease have excessive flatulence when they consume barley, wheat, and rye.
  • Artificial sweeteners: Sorbitol and mannitol are common in candies, chewing gums, and sugar-free sweet foods. Some people develop diarrhea, gas, or both when they consume these substances.
  • Fiber supplements: Adding these too rapidly to the diet can cause flatulence, especially if they contain psyllium.
  • Carbonated drinks: Fizzy drinks and beer may cause a buildup of gas in the intestinal tract.

Anyone concerned about how their diet may be causing flatulence should ask a doctor or a qualified dietitian for advice.

Conditions that can worsen flatulence

Certain health conditions can cause or worsen flatulence.

  • Underlying health conditions: Some chronic conditions can cause flatulence, for example, Crohn’s disease, ulcerative colitis, or diverticulitis. Some types of cancer can lead to a blockage in the intestines.
  • Gallbladder problems: Gallstones and cholecystitis can cause additional gas.
  • Constipation: Feces can make it harder to expel excess gas, resulting in further accumulation and discomfort.
  • Gastroenteritis and other intestinal infections: A viral, bacterial, or parasitic infection of the digestive system, or food poisoning, can cause a buildup of gas. Examples include Escherichia coli (E. coli) infection, amebiasis, and giardiasis.
  • Antibiotics: These can upset the normal intestinal flora, or bacterial flora, in the gut, leading to flatulence.
  • Laxatives: Regular and excessive use of laxatives can increase the risk of developing flatulence.

Other causes include pregnancy, a hernia, pancreatitis, Hirschsprung disease, premenstrual syndrome, endometriosis, and others.

If there are signs of poisoning or a blockage, or if there is blood in the feces, urgent medical attention is needed.

Flatulence is not usually a serious problem. In most cases, a change in lifestyle and diet is all that is needed.

Diet and digestion

Flatulence can be avoided by not eating foods that are likely to cause it, such as those containing high levels of carbohydrates that cannot be absorbed.

Foods containing carbohydrates that are easier to digest include:

Other tips

Other ways to reduce flatulence include:

  • Eating smaller meals: Symptoms often improve if the person eats four to six smaller meals each day rather than three large ones. Peppermint tea may help.
  • Eating slowly: Digestion starts in your mouth, so people must chew foods thoroughly before swallowing.
  • Avoiding gum and carbonated drinks: Chewing gum makes people swallow more air. This can increase flatulence.
  • Not smoking: Smoking causes people to swallow more air, and it can also irritate the digestive system.
  • Choosing low-lactose dairy products: Eliminating foods high in lactose may improve symptoms.
  • Choosing beans that are fermented before cooking: These have less soluble fiber and a higher nutritional content and may decrease flatulence.
  • Doing exercise: Activity enhances the functioning of the digestive system, and this can help reduce gas and bloating.
  • Charcoal pads: Placed inside clothing, these absorb released gas and reduce the impact of foul-smelling gas.
  • Probiotics: These may reduce symptoms in some people.

Lifestyle and dietary changes can often lessen flatulence. Treating any underlying health conditions that may be causing gas production can also help.

However, if these are not enough to remove flatulence, over-the-counter (OTC) medications may help.

Persistent pain and discomfort, social embarrassment, and stress are the main complications of flatulence.

However, it may be a good idea to seek advice if:

  • excess amounts of gas accumulate
  • flatulence occurs frequently
  • symptoms start to become more severe
  • there is a consistently foul smell
  • additional symptoms indicate a possible underlying digestive condition
  • sharp, jabbing pains, or cramps, occur in the abdomen, and the pains change places
  • there is a bloated feeling or knotted sensation in the abdomen

Severe and persistent flatulence can signifyf an underlying condition, such as irritable bowel syndrome (IBS).

A doctor can help discover the underlying cause of flatulence and suggest ways to relieve symptoms.

They will ask the patient about their medical history and dietary habits and carry out a physical exam to determine whether there is any distension in the abdomen. They may check for gas by tapping the abdomen and listening for a hollow sound.

They may ask about bowel movements, whether there is any straining when passing a stool, whether there is abdominal pain after meals, and how long the flatulence has lasted.

This can help decide whether the patient might have a condition that needs treatment.

It may help to keep a food diary for a while before visiting the doctor.

Flatulence is the expulsion of gas via the anal passage. Gas can build up in the digestive system due to the inhalation of air when eating and as a side effect of the breakdown of food by bacteria in the large intestine.

Flatulence is a normal bodily process and happens to most people 8-14 times per day. Foods high in sugars, fiber, and starches are difficult for the body to digest, which can increase digestive gases.

Lifestyle and dietary modifications can reduce the frequency and volume of flatulence.