Flatulence

Introduction 

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This video explains the causes of flatulence (farting) and why certain foods give you gas.

Flatulence is the medical term for passing gas from the digestive system and out of the anus (back passage). Flatulence is more commonly known as ‘passing wind’ or ‘farting’.

Gas can collect in the digestive system in two ways:

  • when a person swallows food, water, or saliva they also swallow a small amount of air, which is mostly made up of oxygen and nitrogen, and
  • when a person digests food, gas is released during the digestive process, mostly in the form of hydrogen, methane, and carbon dioxide.

The body needs to get rid of the build-up of excess gas and does so in two ways:

  • flatulence (farting), and
  • belching (burping).

How common is flatulence?

Flatulence is very common and every living human being experiences it. It is a normal biological process, just like breathing, or sweating on a hot day. Most men will pass wind between14-25 times a day and most women between 7-12 times a day.

Sometimes, you may not notice that you have passed wind because the gases that are passed are usually odorless and are often released in small quantities. The bad smell that is commonly associated with flatulence is caused by trace elements of sulphar gases, which can develop if food has not been properly digested and begins to decompose.

Outlook

If you have excessive flatulence, the problem can usually be controlled by making changes to your diet and lifestyle.

There are a number of medical conditions that can cause symptoms of flatulence, such as constipation, and irritable bowel syndrome (IBS) which is a common, but poorly understood, condition that causes symptoms of indigestion and bloating. 

In these circumstances, medication may be required to help control the symptoms of flatulence while also treating the underlying health condition.


  • show glossary terms
Gut
The sac-like organ of the digestive system. It helps digest food by churning it and mixing it with acids to break it down into smaller pieces.
Oxygen
Oxygen is an odourless, colourless gas that makes up about 20% of the air we breathe.
Stomach
The sac-like organ of the digestive system. It helps digest food by churning it and mixing it with acids to break it down into smaller pieces.
Bacteria
Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and some others are good for you.
Lungs
Lungs are a pair of organs in the chest that control breathing. They remove carbon dioxide from the blood and replace it with oxygen.
Anus
The anus is the opening at the end of the digestive system where solid waste leaves the body.

Last reviewed: 17/07/2009

Next review due: 17/07/2011

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