How much gluten should be consumed prior to being screened for celiac disease?

It’s best to continue a normal, gluten-containing diet before being screened and diagnosed. If a gluten-free diet has been followed for more than a few weeks, then we recommend eating at least 1 serving of gluten (1/2 slice of bread or a cracker, for example) every day for 12 weeks prior to a blood test and 2 weeks prior to a biopsy. This is often referred to as a “gluten challenge” and should be done under the care of a medical professional.