If you are already on a gluten-free diet, but have not had the appropriate testing for celiac disease prior to starting the diet, your doctor may recommend a “gluten challenge” to diagnose celiac disease. The only way to diagnose celiac disease reliably is to eat gluten prior to testing.
When you start a gluten-free diet, antibodies to gluten will start to drop in the blood and the intestine will start to heal, and this can lead to a false negative result. This is why it is so important to not go on a gluten-free diet before the process of testing and diagnosis is complete.
It is very important that a gluten challenge is done under medical supervision. Your doctor will tell you how much gluten you should eat and for how long.
The recommended amount of gluten to consume is usually between 3-10 grams of gluten per day, for a period of 6-12 weeks.
In the Center for Celiac Research and Treatment at Mass General, we usually recommend consuming at least 1-2 slices of bread per day during a gluten challenge. A slice of bread contains about 3.5-5 grams gluten. Another option is to use vital wheat gluten. A tablespoon of vital wheat gluten contains about 7 grams of gluten. It can be mixed in foods such as apple sauce or hot chocolate.
Again, it is very important to do the gluten challenge under the supervision of a doctor. Do not attempt to do it on your own.
Read more about how to find a doctor specializing in celiac disease: https://nationalceliac.org/celiac-disease-questions/is-there-a-state-by-state-register-that-lists-gastroenterologists-who-specialize-in-celiac-disease/
Published April 10, 2023.