- Gas is air in the digestive tract. - Everyone has gas. Burping and passing gas are normal. - Gas in the digestive tract is usually caused by swallowing air and the breakdown of certain foods in the large intestine. - Most foods that contain carbohydrates can cause gas. - Foods that cause gas for one person may not cause gas for someone else. - The most common symptoms of gas are burping, passing gas, bloating, and abdominal pain or discomfort. - Swallowing less air and changing what you eat can help prevent or reduce gas. - Some over-the-counter medicines can help reduce gas. 
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