Gas is made in the stomach and intestines as your body breaks down food into energy. Bloating, which is a feeling of fullness in the abdomen, can make you uncomfortable. Common causes of gas and bloating include: swallowed air, foods and beverages, constipation, medicines or nutritional supplements, a medical condition such as bowel obstruction or Crohn’s disease, or changes in hormone levels. A consultation with your gastroenterologist can help you rule out a medical condition as the cause of bloating and gas.