Stomach gas, also called intestinal gas, is composed of varying quantities of exogenous sources, such as air in the intestine that is passed through the rectum, and endogenous sources, such as gas produced by bacteria within the digestive tracts, including esophagus, stomach and small and large intestines, during the assimilation of sugars and polysaccharides. People may pass rectal gas many times a day, but the volume of gas is different each time. If you experience excessive gas and sharp pain in your lower abdomen, then, it could be a sign of some serious illness and you must seek a doctor's help.
Aerophagia
Air swallowing is a normal part of bodily functions. However, swallowing larger amounts of air, known as aerophagia, or air swallowing, often leads to gastric distention due to the build up of gas in the stomach. Some people unconsciously swallow too much air when eating, chewing gum or smoking, according to the University of Maryland Medical Center.
Breakdown of Certain Undigested Foods
Breakdown of undigested foods is also a cause of gastric trouble. In essence, the body lacks those enzymes needed for the digestive system to assimilate the carbohydrates found in some gassy foods, such as vegetables, legumes, grains, cereals, nuts, seeds and whole-grain breads. As the unabsorbed materials travel to the large intestine, it becomes the food for harmless parasitic bacteria in the colon. (See References 3) Severe gas may be the result of carbohydrate malabsorption or overactive bacteria in the colon, notes the National Digestive Diseases Information Clearinghouse (NDDIC).
Foods That Cause Stomach Gas
Certain foods produce more flatulence than others because they contain considerable amounts of indigestible carbohydrates. By contrast, food containing fats and proteins don't produce very much stomach gas. Most starchy foods, including wheat, corn, noodles and potatoes also create stomach gas when they break down in the large intestine. Insoluble fibers, such as found in wheat bran, pass unabsorbed through the small intestine and produce relatively less gas.
