The digestive system

Digestive phenomena

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A stomach ache is simply pain in the abdomen. It can be difficult to establish the cause of such pains since many illnesses can lead to stomach aches.

Abdominal pain can be linked both to temporary disorders and serious illness.

Abdominal pain can have very different causes, particularly:

  • Gastric reflux
  • Gastro-duodenal ulcers
  • Gastritis

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Stomach aches

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A stomach ache is simply pain in the abdomen. Sometimes its cause is hard to identify. A stomach ache is sometimes associated with a burning sensation, bloating, nausea or even vomiting.


Abdominal pain can have many causes, but here we only cover a few of them. Firstly, there is what we call gastroesophageal reflux. This occurs when part of the stomach contents comes back up into the oesophagus. The stomach wall is covered by a gel-like substance, called ‘mucus’, to protect it from the acidity of the gastric juices. However, the oesophagus does not have this protective mechanism, so it is irritated when the contents of the stomach come back up.

Another cause of stomach ache is peptic ulcers. Peptic ulcers are open wounds that form when the stomach or duodenal wall is destroyed by gastric juices. Since these juices are acidic, they can damage the wall of the digestive tract.

Gastritis can also cause stomach aches. This is an inflammation of the stomach’s mucous membrane, which can be caused by a bacterial infection or even prolonged intake of anti-inflammatories.

If we eat a high-fat meal, the liver synthesises a large amount of bile salts. If the liver cannot make enough bile salts, we may suffer from digestive problems, such as abdominal pain or diarrhoea. You may have heard this called an upset stomach.

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