The number of people adhering to a gluten-free diet more than tripled between 2009 and 2014, despite the fact that the prevalence of celiac disease has remained largely stable over the same period, according to data from the National Health and Nutrition Examination Survey.

Hyun-seok Kim, MD, MPH, and colleagues from Rutgers New Jersey Medical School noted that there is a popular trend of people choosing gluten-free diets, which exceeds the numbers that would be solely attributable to an increasing prevalence of celiac disease.

In a report published online Sept. 6 in JAMA Internal Medicine, the researchers noted that of 22,278 persons aged 6 years or older for whom data were available on celiac disease status and gluten-free diet status, 106 (0.69%) had a diagnosis of celiac disease, and 213 (1.08%) followed a gluten-free diet but did not have celiac disease.

At a U.S. population level, this would correspond to an estimated 1.76 million individuals with celiac disease, and 2.7 million individuals without celiac disease who follow a gluten-free diet.

The prevalence of celiac disease ranged from 0.70% during 2009-2010, to 0.77% during 2011-2012, and 0.58% during 2013-2014 (JAMA Intern Med. 2016 Sept 6. doi: 10.1001/jamainternmed.2016.5254 ).

In contrast, the prevalence of a gluten-free diet without celiac disease increased from 0.52% during 2009-2010 to 0.99% during 2011-2012 and 1.69% during 2013-2014, although the increase was even greater among non-Hispanic whites.

“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,” they reported.

The authors suggested that there were a number of reasons why individuals without celiac disease might choose to follow a gluten-free diet. “The public perception is that gluten-free diets are healthier and may provide benefits to nonspecific gastrointestinal symptoms,” they wrote, pointing out that gluten-free products are now also more widely available in supermarkets and online.

“There is also an increasing number of individuals with self-diagnosed gluten sensitivity but not the typical enteropathic or serologic features of celiac disease who have improved gastrointestinal health after avoidance of gluten-containing products.”

They stressed that the numbers of individuals in the survey with celiac disease or adhering to a gluten-free diet were relatively small, and that a diagnosis of celiac disease was not confirmed by intestinal biopsy, relying instead on serological tests and prior diagnosis by a health professional.

No conflicts of interest were declared.