Why does coeliac disease cause unintentional weight loss?

The small intestine has a folded lining that helps the body take in nutrients. In coeliac disease, an immune response to gluten can injure this lining. Food may still be eaten, yet less of its energy, iron, vitamins, and other nutrients may be absorbed. Diarrhoea, nausea, abdominal discomfort, or a reduced appetite can further limit intake. Unintentional Weight Loss is a common presentation of Coeliac Disease, although weight loss can also arise from many other medical and practical causes.

Unplanned weight loss deserves a clinical review. If coeliac disease is being considered, ask about testing before changing to a gluten-free diet; removing gluten first can make the results harder to interpret. Bring a note of changes in appetite, stools, nausea, abdominal symptoms, and foods you avoid. After a diagnosis, a clinician or dietitian can help you build a nutritionally complete gluten-free diet and check for problems that may be contributing to continued weight loss.

Make a prompt appointment if your weight continues to fall without trying, you are struggling to eat or drink, or weakness is affecting daily life. Seek urgent care for severe abdominal pain, repeated vomiting, fainting, confusion, black stools, or blood in vomit. Children, older adults, and people who are pregnant should contact a clinician early when eating becomes difficult or weight is falling.

Ask which tests can check for coeliac disease, whether you should keep gluten in your diet before testing, and whether you need checks for nutritional deficiencies. If coeliac disease is confirmed, ask how to monitor recovery and when dietetic support would help.