But other parts of the digestive tract are more likely to develop cancer. One possible cause for cancers of the digestive tract is exposure to many different chemicals in food. In addition, inheriting certain genes is known to make specific kinds of digestive system cancer more likely. Sometimes the valve between the esophagus and the stomach does not close properly. In that case stomach flu ids may enter the esophagus and produce the burning sensation known as heartburn .
Many events can cause the lining of the digestive tract to become irritated.
The most common cause is the infection gastroenteritis caused by a virus, a disease commonly called the flu although it is different from influenza . A much more severe diarrhea, which can be fatal, is caused by the bacteria of typhoid fever or of cholera . In many persons either the stomach or the duodenum develops sores called ulcers . It is now known that these sores are caused by the action of a specific bacterium. Conditions that affect the liver or gallbladder interfere with digestion.