An analysis of published studies looking at products labelled gluten-free, foods that are naturally gluten-free and gluten free meals prepared in food services has indicated that over 15 per cent of these products contain gluten at levels greater than 20 mg/kg.
Forty articles were included in the review, drawn from a literature search of Scopus, Science Direct, Web of Science, PubMed, and Google Scholar. Of the three categories, a greater proportion of naturally gluten-free foods contained gluten (over 28 per cent) than labelled gluten-free products (9.5 per cent) and meals in food services (almost 5 per cent).
Oats were the most common source of unintended gluten content in gluten free foods but overall, the prevalence of unintended gluten in gluten free foods has significantly decreased over time.
Most of the studies identified for inclusion in this review were carried out in upper-middle-income and high-income countries, while only one study was conducted in lower-middle income countries.
Further activities at an industry level are required to avoid the presence of gluten in foods that are naturally gluten free or are labelled gluten free, including in low-income countries.
Reference: Guennouni et al. 2021. British Journal of Nutrition. DOI: 10.1017/S0007114521002488.