The full answer
A supervised, temporary return to eating gluten
A gluten challenge is when someone who has already reduced or stopped eating gluten deliberately reintroduces it — under medical guidance — for a period of time (often several weeks) before celiac disease testing, so blood tests and biopsy results are accurate.
Why it should be doctor-supervised
The exact amount and duration recommended varies by individual situation, which is why a gluten challenge should be planned with a doctor rather than done informally — see whether to stop eating gluten before testing for the broader context.
Important context
Individual symptoms, reactions, medical histories, food products, and local labeling rules can vary. Community experiences are not medical evidence.
For personal medical decisions, diagnosis, testing, or treatment, consult a qualified healthcare professional.