Causes

Excess upper intestinal gas can result from swallowing more than a usual amount of air, overeating, smoking or chewing gum. Excess lower intestinal gas can be caused by eating too much of certain foods, by the inability to fully digest certain foods or by a disruption in the bacteria normally found in the colon.

Foods that cause excess gas

Foods that cause gas in one person might not cause it in another. Common gas-producing foods and substances include:

• Beans and lentils
• Vegetables such as cabbage, broccoli, cauliflower, bok choy and Brussels sprouts
• Bran
• Dairy products containing lactose
• Fructose, which is found in some fruits and used as a sweetener in soft drinks and other products
• Sorbitol, a sugar substitute found in some sugar-free candies, gums and artificial sweeteners
• Carbonated beverages, such as soda or beer

Digestive disorders that cause excess gas

Excessive intestinal gas — belching or flatulence more than 20 times a day — sometimes indicates a disorder such as:

• Celiac disease
• Colon cancer
• Constipation
• Crohn's disease (a type of inflammatory bowel disease)
• Diabetes
• Dumping syndrome
• Eating disorders
• Functional dyspepsia
• Gastroesophageal reflux disease (GERD)
• Gastroparesis (a condition in which the muscles of the stomach wall don't function properly, interfering with digestion)
• Inflammatory bowel disease (IBD)
• Intestinal obstruction
• Irritable bowel syndrome
• Lactose intolerance
• Ovarian cancer
• Pancreatic insufficiency
• Peptic ulcer
• Ulcerative colitis (a type of inflammatory bowel disease)