Celiac disease—an autoimmune disorder affecting the small intestine and caused by a reaction to gluten—is not new; it was first described by Aretaeus, a Greek physician who lived 2,000 years ago. However, despite being around for thousands of years, the last decade or so has seen celiac disease take center stage.
This revival of sorts may have more to do with perception than reality; then again, eventually, perception becomes reality if enough people believe it. Case in point: the report “Time Trends in the Prevalence of Celiac Disease and Gluten-Free Diet in the US Population: Results From the National Health and Nutrition Examination Surveys 2009-2014.”
The report, published in the Journal of the American Medical Association (JAMA) in 2016, found two interesting trends with regard to celiac disease: While the prevalence of celiac disease remained fairly stable during the time period observed (0.7% of the nearly 23,000 subjects in 2009-10, 0.77% in 2011-12, 0.58% in 2013-14), the prevalence of strict gluten-free diet adherence rose significantly, from 0.52% in 2009-10 to 1.69% in 2013-14.
The authors of the report, noting this discrepancy, said, “Our findings suggest that the prevalence of celiac disease has remained stable in the US population from 2009 through 2014, although increasing numbers of people are now following gluten-free diets. The two trends may be related because gluten consumption has been identified as a risk factor of celiac disease, such that steady or even decreasing gluten consumption may be contributing to a plateau in celiac disease.”
Could this be true? Could concerns about gluten intake and celiac disease, even among those not diagnosed with the condition, actually lead to a decrease in the condition itself? According to a new observational study published in August 2019, that may just be the case.
The study, also published in JAMA, is called the most comprehensive of its kind and followed 6,600 children in Sweden, Germany, Finland and the U.S. considered to be at increased risk of developing celiac disease.
“Our study shows a clear association between the amount of gluten the children consumed and the risk of developing celiac disease or pre-celiac disease,” said Daniel Agardh, associate professor at Lund University and consultant at Skåne University Hospital in Malmö, and leader of the study. “This confirms our earlier findings from studies on Swedish children.”
The findings showed that even a small amount of gluten intake in these higher-risk children could have a huge effect on likelihood of developing the disease.
“A daily gluten intake over 2 grams at the age of 2 was associated with a 75% increase in risk of developing celiac disease,” said Carin Andrén Aronsson, lead author of the report and dietician at Lund University, noting that 2 grams is about the equivalent to one slice of white bread. “This is in comparison with children who ate less than 2 grams of gluten.”
Aronsson was sure to note, however, how difficult it may be to nail down recommendations due to the high variability of gluten and gluten responses.
“[D]etermining a recommendation or limit is a challenge as gluten intake varies and increases during the first years of life,” she said.
The report noted the association between early gluten intake and higher celiac risk was seen in all participating countries but Germany, which did not have sufficient data to draw conclusions. It also noted that this study investigated only total gluten intake, with the next logical step being to delineate which gluten-containing food groups are of greater significance compared to others for the development of celiac disease.
Though celiac disease prevalence does seem to have plateaued somewhat over the last decade, the number of people actively avoiding gluten has clearly increased during that time. If, as the data from August’s study indicate, decreased gluten intake in children leads to fewer celiac disease occurrences, those two numbers seem primed to continue to move in opposite directions.