Gluten finds its way into gluten-free diets, especially on weekends

A new study has found that people with coeliac disease who are on a long-term gluten-free diet are still frequently exposed to gluten.

Using gluten immunogenic peptides (GIP) in faecal and urine samples as a marker of gluten exposure, researchers in Argentina studied samples collected from 53 adults with coeliac disease who had been following a gluten-free diet for more than two years.  Stool samples were collected each Friday and Saturday and urine samples each Sunday for the 4-week study duration.

Almost 40 per cent of the samples were positive for GIP, with close to 90 per cent of participants having at least one positive sample throughout the study. On weekends (urine samples), 69.8 per cent of patients excreted GIP at least once, compared with 62.3 per cent during weekdays (stool). Those experiencing symptoms of coeliac disease had more weeks in which GIP was detected in stool than patients without symptoms.

The researchers suggest that inadvertent gluten exposure, particularly during weekends, might explain the persistence of symptoms despite adherence to a gluten-free diet. They hope their findings may lead to the development of new strategies to improve long-term dietary monitoring.

Reference: Stefanolo et al. Clinical Gastroenterology and Hepatology 2020.
DOI: 10.1016/j.cgh.2020.03.038.