Causes of intestinal and stomach gas include swallowing large amounts of air, eating gas-producing foods and digestive conditions, according to Mayo Clinic. Gas in the lower intestine is a byproduct of stomach gas.
Foods that cause stomach gas include lentils, beans, dairy products with lactose, and fruits or sweeteners that contain sorbitol or fructose, explains Mayo Clinic. These foods contain substances that the body cannot fully digest until getting to the lower intestine. At this point, the food breaks down into different substances, such as gas.
If the gas is excessive, more than 20 times each day, it is likely not due to food but instead from a disease or condition, claims Mayo Clinic. These diseases or conditions include celiac disease, food allergies, gastroesophageal reflux disease and irritable bowel syndrome. People who have gas may also suffer from peptic ulcers or lactose intolerance.
Intestinal gas is rarely a sign of a serious condition, but it can cause embarrassment and discomfort, states Mayo Clinic. In most cases, gas is a sign that the digestive system is working correctly. If a person is dealing with excessive gas, a diet change is the first step in treatment. If the gas is severe or doesn't change after a diet change, a person should see a doctor.