Kristin Voorhees, Healthcare Relations Manager at the National Foundation for Celiac Awareness, caught up with renowned celiac researcher, Joseph A. Murray, MD of the Division of Gastroenterology & Hepatology and Department of Immunology at The Mayo Clinic, to discuss the implications of adopting a gluten-free diet prior to being tested for celiac disease.
What do you suggest to people who have put themselves on a gluten-free diet without prior testing?
My general advice is as follows:
If someone feels they might have a problem with gluten, they should seek testing for celiac disease first. It is important that they not ask for a screening for celiac disease, as this is not a diagnostic test and most often not covered by insurance companies. However, if they have complaints, such as abdominal bloating, diarrhea, etc., then this is not a screening test, it is a diagnostic test for the indication of possible celiac disease. The testing should be done before there is any change in diet. If the patient has already changed their diet for a week or two, they should go back on gluten for at least the same length of time. This should be adequate full gluten ingestion, not simply small amounts of gluten in order to reduce the risk that the test will be false negative. For patients who have gone on a gluten-free diet and have been on it for many months and who had quite severe illness before doing so, they may need to consider a gluten challenge but only under medical supervision. There are a couple tests that might be done in patients without a gluten challenge–for example, a genetic test might be helpful—to identify if they do not carry the genetics required for celiac disease. In this circumstance, you can rule out the possibility of celiac disease. Patients will often ask me, “Why bother checking for celiac disease if I feel better on a gluten-free diet? Why do I need to be concerned?” The issues I see are several:
What if the patients who had substantial chronic symptoms, were tested for celiac disease, were found to be negative, and went on a gluten-free diet from which they have derived some substantial benefit?
They may well have non-celiac gluten sensitivity. In order to fulfill the definition of this, it is first necessary that celiac disease was checked for and ruled out, secondly that their symptoms have largely or completely responded to a gluten-free diet, and that response is durable—it is not just a short-term placebo response. For such patients, I certainly don’t object to them being on a gluten-free diet if they derive symptoms benefit from it.
Finally, I am concerned about patients who undertake multiple food avoidances for various reasons, and there is an eating disorder called orthorexia where people avoid multiple foods without clear reason why, and often lead themselves in to severe malnutrition. Hopefully, those occurrences are pretty rare, but nonetheless pretty important.
– Joseph A. Murray, MD
Division of Gastroenterology & Hepatology
Department of Immunology