what causes gas and bloating

Gas and bloating can be caused by a variety of factors, including swallowing air when eating or drinking, eating gas-producing foods, and medical conditions. Excess gas is often a symptom of chronic intestinal conditions such as diverticulitis, ulcerative colitis, or Crohn's disease. Other causes include small bowel bacterial overgrowth, food intolerances, irritable bowel syndrome (IBS), and constipation. In some cases, gas and bloating can also be caused by swallowing air, eating too quickly, or drinking carbonated beverages