Rule out the serious stuff first.

If it happens on most days for three weeks or more, or comes with unintended weight loss, blood in your stool or black stools, persistent vomiting, difficulty swallowing, a change in bowel habit lasting weeks, unexplained fatigue or anaemia — or if you're over 50 with new symptoms. Persistent bloating is specifically on the list doctors want to assess, particularly in women over 50. Restricting food first can delay finding the cause.

Because coeliac blood tests rely on you still eating gluten. Removing it first can produce a false result and delay a real diagnosis for years. If gluten is a suspect, ask your doctor about testing before you change anything — the guide won't design a gluten-free week for you until that's sorted.

Days 1-4: keep a diary and change nothing, so there's a baseline. Days 5-11: remove one or two likely suspects drawn from your own diary, with normal meals built around what's left. Days 12-14: reintroduce one food at a time in a normal portion, waiting two to three days each. Elimination without reintroduction is just restriction.

Very often it isn't. Eating quickly, fizzy drinks, chewing gum, sugar-free sweeteners like sorbitol and xylitol, constipation, stress and the menstrual cycle all bloat people, and all cost nothing to test. If the elimination week changes nothing, the answer isn't cutting more foods — it's going back to a doctor with your diary.

Then this isn't the right tool, and stopping is a reasonable choice. Elimination diets can worsen a difficult relationship with food, and a shrinking list of safe foods is a sign to get support rather than restrict further. A doctor or registered dietitian can help you approach it safely — a full low FODMAP approach in particular is normally done with a dietitian.