Gas & Bloating

What causes gas and bloating?

Increased air within the gastrointestinal (GI) tract is frequently felt as excessive belching, bloating, abdominal distention or flatulence. The passing of gas and belching are normal bodily functions and the amount of produced depends largely on diet and individual factors.


What are the sources of gas?

There are two main sources of intestinal gas - air swallowing and bacterial production. Air swallowing normally occurs while eating or drinking. Swallowing large amounts of air can occur with rapid eating, gulping of liquids, chewing gum, drinking through straws and smoking. Drinking carbonated beverages can also be a source of increased gas within the intestinal tract.

Gas can also be produced within the intestinal tract when normal gut bacteria digest certain food products. Many individuals lack certain enzymes required to break down carbohydrates within the intestinal tract. As a result, these undigested carbohydrates are digested by gut bacteria leading to gas formation. One of the more common deficiencies is a lack of lactase enzyme, the enzyme required to digest lactose. Lactose is the sugar found in milk and milk-based dairy products. Deficiencies in lactase can lead to gas, bloating, abdominal cramping and diarrhea after dairy consumption.


What are common foods related to gas formation?

There are many foods associated with increased gas production within the intestinal tract. Many of the foods are high in Fermentable Oligo-Di-Monosaccharides and Polyols (FODMAPs). FODMAPs are osmotic and pull water into the intestinal tract. They are frequently poorly digested and are fermentedby bacteria in the gut leading to gas production. Some common foods that are gas forming include:

• Broccoli
• Brussel sprouts
• Cauliflower
• Garlic
• Onions
• Foods containing high fructose corn syrup (HFCS)
• Artificial Sweetners

• Beans
• Watermelon
• Apples
• Milk and milk-containing products


How is gas and bloating diagnosed?

A comprehensive history and physical examination is the first step in diagnosing the cause of gas and bloating. At times, further testing is not required. An elimination diet may be used to determine if there are any specific food intolerances. Blood and stool testing may be performed to evaluate for celiac disease, fat in the stools (steatorrhea) or intestinal infections. A lactose breath test may be used to diagnose lactase deficiency. A specialized breath test to diagnose small intestinal bacterial overgrowth is also frequently used in the work up of gas and bloating. At times, examining the intestinal lining with an endoscopy, video capsule endoscopy or colonoscopy may be required.


What are the treatments of gas and bloating?

• Dietary modifications - Avoiding foods that trigger symptoms
• Simethicone containing products - Gas-X ®, Maalox Anti-Gas ®, Phazyme ®
• Enzyme supplements - Lactaid ® and Beano ®
• Activated charcoal
• Pepto Bismol ® - Can reduce the odor of foul smelling gas

The information provided above is meant to be used as an informative guide for patients. For precise and individualized recommendations, please consult with one of our board certified gastroenterologists to discuss your symptoms.

For additional information or to book an appointment at the Gastroenterology Center of New York, please feel free to reach out to our dedicated team by calling us at 718-210-2960. You can also schedule online or reach out to us via the Contact Us form.

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