What causes indigestion?

When you eat, your stomach produces acid juices to break down and digest your food. These juices are usually kept inside the stomach by a muscle at the bottom of the oesophagus (the tube that links the mouth to the stomach) which tightens and closes. Occasionally, the acid juices can be squeezed up into the oesophagus, causing a 'burning' sensation in the chest. This feeling is often known as heartburn.

Sometimes, tiny bubbles of gas may collect in your stomach. This may be air you have swallowed, or gases formed by the normal action of your stomach. Your body can usually release these bubbles, for example, by burping, but small ones can get trapped and leave you feeling uncomfortable, bloated, 'gassy' or wanting to burp.

At other times the normal action of your stomach, which digests food and passes it into the intestine, may slow down, causing food to stay in your stomach too long. This can make you feel full, heavy and bloated.

Although your stomach needs acid to digest your food, too much acid can cause stomach ache and pains.