What causes bloating?

Gas may build up after fizzy drinks, eating quickly, chewing gum, or fermentable foods. Constipation can stretch the abdomen because stool and gas move slowly. Lactose intolerance and other food intolerance can cause bloating with cramps or loose stools after particular foods. Irritable bowel syndrome may combine bloating with abdominal pain and altered bowel habits. Coeliac disease, giardiasis, or Helicobacter pylori infection are other possible causes when symptoms persist or come with diarrhoea, weight change, or upper abdominal discomfort.

The timing matters: record meals, bowel movements, pain, stool changes, and any relation to your menstrual cycle. Read about [Bloating](/symptoms/bloating/) for a fuller description of the symptom.

Try eating slowly, reducing fizzy drinks, taking gentle movement, and treating constipation with advice from a pharmacist or clinician. Keep a short food-and-symptom diary rather than removing many foods at once. A clinician or [Nutrition Counselling](/treatments/lifestyle-and-wellness/nutrition-counselling/) service can help identify patterns while keeping meals balanced. Do not start a gluten-free diet before coeliac testing without discussing it, because this can affect test results.

Arrange assessment if bloating is persistent, keeps returning, or is accompanied by unexplained weight loss, ongoing vomiting, blood in stool, fever, a new lump, or a major change in bowel habit. Seek urgent care for severe or rapidly worsening pain, a swollen rigid abdomen, repeated vomiting, or inability to pass stool or gas.

Ask which symptoms suggest [Food Intolerance](/conditions/food-intolerance/), [Lactose Intolerance](/conditions/lactose-intolerance/), [Irritable Bowel Syndrome](/conditions/irritable-bowel-syndrome/), or another cause; whether testing is needed; and how to manage constipation or diet changes safely.