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:
- If the person really has celiac disease, then they need medical follow-up. The disease consists of severe inflammation in the intestine and it is very important to make sure that it heals and it recovers.
- If the person really has celiac disease, then the family members need to be checked for celiac disease as it can commonly occur in other family members, have significant consequences, and frequently is not diagnosed.
- Going on a gluten-free diet is not specific. There are many reasons that going on a gluten-free diet may make people feel better—for example, eating less junk food—and these effects may be temporary and indeed it may be that their symptoms recur despite continuing to try to be gluten-free leading to more diagnostic mystery.
- Delay of other diagnoses. Going on a gluten-free diet, especially if this is tried for several weeks or months, may delay an alternative diagnosis, which sometimes can be a significant illness for which quite different medical therapy is necessary.
- There may be some nutritional deficiencies that can occur on a gluten-free diet, such as less fiber, which can lead to bowel problems such as constipation, some reduction in nutrients that typically added to gluten-free cereals or breads that are not added to gluten-free alternatives.
- There is a substantial increased cost. A particular situation is where the gluten-free diet is essentially imposed on a child without strong evidence for medical necessity. This will lead to problems, especially when the child grows up and finds themselves in many different situations.
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