Pushing the Gluten-Free Envelope: First Steps Towards Evidence-Based Gluten-Free Diet Recommendations.

E ven the most strict gluten-free diets are unlikely to be truly 100% gluten-free (1). Prior literature has defined safe thresholds of gluten exposure for individuals with celiac disease that have helped guide the Codex Alimentarius recommendation for the international gluten-free safety cut-off of 20 ppm (mg/kg) (2,3). Although it is clear that people with celiac disease should never knowingly eat gluten-containing foods, the risk and amount of exposure to gluten from day-to-day life (such as in a shared kitchen or at school) is unknown (4,5). Though well-intentioned, the current recommendations of avoiding all potential sources of cross-contact (however, small) may breed a culture of hypervigilance (6). Without clear evidence for safe school-based practices, this hypervigilance may extend to school-time activities. Many parents and children worry about gluten exposure during school, the potential uncomfortable and embarrassing symptoms caused by cross-contact, as well as possible long-term medical complications of poor adherence to the gluten-free diet (7,8). This fear can ultimately lead to social isolation and decreased quality of life. With over 1 in 100 school-aged children now affected by celiac disease, we desperately need better evidence to guide parents and educators on school policies (9). In this issue of the Journal of Pediatric Gastroenterology and Nutrition, Weisbrod et al test common school projects by examining gluten transfer during common activities that use wheat-based products including Play-doh, baking chocolate chip cookies, paper mâché, and cooked or dry pasta at a sensory table. Gluten transfer was measured by rubbing gluten-free bread on the participating children’s hands and on activity surfaces after completing the activity both before and after an assigned cleaning method. This was done to emulate performing a school activity with gluten-containing products and subsequently eating a gluten-free snack or lunch. Gluten content was quantified using a R5 sandwich ELISA. Observed gluten transfer was less than 20 ppm for both Play-doh and dry pasta. Baking chocolate chip cookies resulted in almost always greater than 20 ppm transfer of gluten onto the children’s hands and the baking surface, although this was preventable with thorough handand surface-washing techniques. The paper mâché and cooked pasta projects also resulted in a high likelihood of greater than 20 ppm transfer of gluten to the child’s hands. Although this amount of ingested gluten would be potentially harmful to children with celiac disease, it is of minimal risk if not ingested. Thus, for a child with celiac disease who is developmentally able to appropriately wash his or her hands after projects and before eating, as well as refrain from ingesting materials like Play-doh while playing with them, some commonly restricted activities may actually be safe. By identifying common school activities with high versus low risk of gluten contamination, we are better informed to make evidence-based guidelines and 504 plans to not only help parents and educators protect children from substantial gluten exposure but also prevent unnecessary exclusion from safe activities. This article parallels the authors’ recent publication in Gastroenterology that examined cross-contact in common food preparation scenarios and suggested that the use of a shared toaster, knife, and pot with adequate cleaning practices may be safe for children with celiac disease on a gluten-free diet (10). This study does not suggest that people with celiac disease should seek out higher risk situations or intentionally eat gluten but rather provides some reassurance that occasional small potential exposures may not be as clinically significant as we have long feared. As degree of gluten sensitivity may be variable among those with celiac disease (2,11), these groundbreaking studies are the first step in defining safe yet pragmatic gluten-free practices. Ultimately, a better understanding of cross-contamination risks may lead to less hypervigilance and improved quality of life. Updated, evidence-informed education on the gluten-free diet can lead to less confusion for families and more comfort that their children can participate in all activities, with only necessary modifications taken. For many years, the question asked with celiac disease is ‘‘How strict is strict enough?’’ but perhaps it is equally important to ask ‘‘How strict is too strict?’’ Although this remains an exciting era for pharmacotherapeutics in celiac disease, perceived celiac disease treatment burden remains higher than many other chronic diseases, and we cannot wait for a new therapy to improve our patients’ quality of life (12). Continued evaluation of the gluten-free diet and risk of crosscontact is warranted for the development of evidence-based school guidelines and to improve the psychosocial burden of celiac disease.