Passing out gas, either through the mouth as a belch (burp) or the rear as flatus, is a normal process. It is a result of gas being trapped or produced within the upper or lower part of the gut. Although often seen as an embarrassing event, there is sometimes more to a belch than may be evident. When belching is excessive or of a particularly foul odor, it may be considered as a symptom of an underlying disease. As some of these diseases are more likely to occur in seniors, it is important to view the ‘burpy old person’ from a medical perspective.

Normal Causes of Belching

The most common cause of belching is air that is trapped in the upper gut. This air is swallowed especially when eating, with chewing gum, cigarette smoking and eating and talking too fast. This air swallowing is known as aerophagia.

Apart from trapped gas, chemical processes with the action of digestive enzymes and the breakdown of food by bacteria in the gut are also sources of gas. Lower down, even gas in the bloodstream can pass out into the gut and contribute towards flatus. However, the gas passed out during belching is almost entirely trapped air.

Carbonated beverages and some foods that tend to increase gas production in the gut may also be responsible. Some of the common gassy foods include beans, cabbage and other vegetables, whole grains and legumes. Many other foods are also known to be gassy but not may be as much of a problem in every person.

Excessive Belching and Burping

Despite burping being considered normal, sometimes even when it is frequent, there comes a point where it is excessive. In these instances belching may not only be uncontrollable and embarrassing, but can cause significant discomfort, hamper normal eating, promote acid reflux and even affect sleep.

There are a host of diseases that can present with excessive belching as a symptom. Most of these are related to food intolerance or abnormally slow movement of food in the upper gut. However, the more likely causes of belching like excessive air swallowing or eating large amounts of gassy food should be first considered.

Some of the diseases associated with excessive belching includes :

• Food intolerance and malabsorption – lactose, gluten, fructose, sorbitol
• Gastritis
• Gastroparesis
• Gallbladder disease
• Hiatal hernia
• Inflammatory bowel disease, particularly Crohns disease
• Intestinal obstruction
• Irritable bowel syndrome (IBS)
• Pancreatitis
• Peptic ulcers
• Small intestinal bacterial overgrowth

Foul Smelling Belching

Belches are rather unpleasant in odor but not as offensive as flatulence. This is largely due to the fact that the food in the upper gut has not decomposed and fermented to the extent that it does in the lower gut. However, unusually foul smelling belches may be a cause for concern even if belching is not excessive.

It may arise with conditions such as :

• Clostridium difficile infection
• Gastric outlet obstruction
• Gastroparesis
• H.pylori infection
• Small intestinal bacterial overgrowth

Sometimes the source of the foul odor is not from the gut but instead from the throat and even the lungs in the case of a lung abscess.

However, before a pathological (disease) cause is suspected, first foods and lifestyle measures need to be considered and excluded. Certain foods have a higher sulfur content which are more likely to promote foul smelling belches. Sometimes it may be naturally occurring sulfur, as in meat, eggs and dairy, while at other times it may be due to artificial additives and preservatives. Therefore the first step in assessing any belching-related problems is to change the diet to simple foods that are less likely to cause excessive belching or foul smelling burps.