A noisy stomach is typically caused by gas. It is gas that causes a person to burp or emit noises from another, more embarrassing, end of his body. It is also responsible for stomachs that growl or rumble, often at the most embarrassing moments. No one is exempt from gas, but some people seem to have noisier stomachs than others.
The gas that creates so much noise is typically caused by swallowing air; the rest of it may form as a normal part of digesting food. While most people don’t swallow air on purpose, many swallow quite a bit of it while doing ordinary things. For example, many people swallow air while talking. Those who inhale through the mouth while talking tend to swallow more of it, and people who gasp excitedly while speaking may take in even more. This can lead to burping that seems excessive and a very noisy stomach.
People also tend to swallow air while they eat. This is particularly true of those who eat and talk at the same time. A person is also likely to swallow air while smoking and chewing gum. Drinking through a straw and wearing dentures that don’t fit well can also lead to this issue, as can drinking a lot of soda and other beverages that are carbonated.
In some cases, a medical condition contributes to air swallowing and the development of a noisy stomach. For example, a person may have an allergy that causes mucus to drip from the nasal area and down his throat. He may swallow often, taking in some air along with the mucus he is swallowing; those with heartburn may swallow when backwashes of stomach acid move up into the esophagus. In the process of swallowing to move it back down to the stomach, they may also swallow some air. Some people just swallow more than others, often as part of a nervous condition; this causes more air to build up and make noise in the stomach.
Most people equate a noisy stomach with hunger, which is correct, but the noisemaker may not be the stomach after all. The unpleasant sounds may be the swallowed air moving in the intestine. Additionally, foods that tend to produce more gas than others contribute to stomach and/or intestinal noise. Such foods include those that are fiber rich, including many types of fruits and vegetables. Beans are notorious for contributing to gas; even juices and foods containing sorbitol, a sweetener, can contribute to gas.