Flatulence (gas) can occur in both the upper and lower intestines. Gas in the upper intestines can occur when swallowing too much air while eating, drinking or even chewing gum and is passed through belching. Gas in the large intestine is formed during the normal bacterial breakdown of undigested foods. Everyone has gas and gas pains with the typical person expelling intestinal gas (flatus) 12 or more times per day. Gas that is not expelled can cause intense intermittent abdominal pain. Once flatus is expelled the abdominal pain subsides. Intestinal gas is a combination of oxygen, nitrogen, hydrogen, carbon dioxide, and methane.
When we eat, drink or swallow saliva, we also swallow tiny amounts of air. This swallowed air accumulates in the gut. The gas within our digestive system consists mainly of nitrogen and oxygen.
When we digest food, gas, mainly in the form of hydrogen, methane and carbon dioxide is released. As the gas builds up, the body may need to get rid of it – this is done by either burping (belching) or flatulence (farting).
Many times, flatulence occurs and the person is unaware of it – there is no smell, and the amount is tiny. When there is a smell, there are usually small amounts of sulfur gases. If food has not been digested properly, it starts to decompose (rot), releasing sulfur.
Flatulence can have several natural causes, and may also be the consequence of a condition that affects the digestive system.
Intestinal gas consists of:
• Exogenous sources – air that comes in from outside. We swallow it when we eat, drink or swallow saliva. It can occur when we experience nausea or acid reflux and excess saliva is produced.
• Endogenous sources – it is produced within the gut. Gas may be produced as a by-product of digestion of certain foods, or when foods are not digested completely. Anything that causes food not to be digested completely by the stomach and/or small intestine can cause flatulence when it reaches the large intestine.
Lower intestinal flatus is formed when bacteria in the colon ferment carbohydrates that are not digested in the small intestine. Healthy foods such as beans, fruits, grains and legumes are often the worst offenders because they are high in fiber. Other causes of excess gas include carbonated beverages such as beer and soda, diseases of the large intestine, antibiotics, laxatives, constipation, food intolerances, and artificial additives. Anything associated with constipation can lead to flatulence as well