If you have celiac disease or gluten sensitivity, be warned: more than half of certain gluten-free restaurant meals tested positive for gluten in a number of tests. The analysis was part of a newly published study that sought to evaluate the risk individuals with celiac disease face when they eat out. The results were concerning, particularly for individuals who are sensitive to even tiny amounts of gluten.
Why does gluten matter?
Celiac disease is an autoimmune disease that causes an immune reaction when someone with the condition consumes the protein gluten. As well, and not without some controversy, some people report adverse effects from consuming gluten even in the absence of a celiac diagnosis; this is referred to as gluten intolerance and gluten sensitivity.
Gluten is found in barley, wheat, and rye, three very commonly used food ingredients. As a result, gluten is often present in the majority of packaged food products and restaurant meals.
Due to the huge uptick in gluten awareness toward the start of the decade, many people transitioned to a gluten-free diet. This was viewed as a diet trend and openly mocked by cynics, resulting in some restaurants and chefs not taking gluten-free requests seriously. As well, many restaurants and pizza joints now offer “gluten-free” products to capitalize on the diet trend, but don’t promise an actually gluten-free product due to preparing all food in the same kitchen.
New study has bad news
A study recently published in the American Journal of Gastroenterology reports that more than half of pasta and pizza dishes served in restaurants tested positive for gluten despite being advertised as gluten-free. As well, approximately 30% of food products advertised as gluten-free had detectable levels of gluten in tests.
Overall, tests on 5,624 supposedly gluten-free food items over the course of 18 months tested positive for gluten in 32% of cases.
Some meals more risky than others
Though the overall results showed that around one-third of gluten-free meals contain gluten, some dishes were more likely to test positive than others. Pizza was the biggest offender with 53% of gluten-free samples testing positive for gluten. Pasta came in with a close second place at 51%. The startling figures indicate that the majority of gluten-free pizza and pasta meals may actually contain gluten.
In other cases, the general “dinner” meals category resulted in positive tests 34% of the time, “lunch” was positive 29% of the time, and breakfast meals were positive in 27% of tests. Though the findings are less severe than in pizza and pasta dishes, the study indicates that more than a quarter of gluten-free restaurant meals may ultimately contain detectable levels of gluten.
Why is gluten present?
Researchers suspect the presence of gluten in supposedly gluten-free restaurant meals may primarily be due to contamination. Though a restaurant may cook a meal that doesn’t contain any gluten products, the risk for cross-contamination is high if the food is not prepared in a separate cooking area.
The study’s findings were based on data gathered by a portable device called the Nima Gluten Sensor. This device enables celiac patients to test restaurant food for gluten; it is very sensitive and that sensitivity, among other things, may have contributed to the high gluten detection numbers.
The study’s Benjamin Lebwohl, MD, MS, explained:
Users may have uploaded results that surprised them the most. The device can detect levels as low as 5 to 10 ppm, which most do not consider clinically significant, so a ‘gluten found’ result does not necessarily mean ‘unsafe for celiac disease.’ The device also does not detect certain forms of gluten, such as fermented gluten. So both false positives and false negatives will affect this estimate.
What can you do?
Customers should inquire about whether gluten-free foods are prepared in a separate cooking area in order to make an informed choice about their meal. Restaurants that cannot guarantee a gluten-free experience are best avoided by celiac sufferers and individuals with high gluten sensitivity. Alternatively, customers can order the meal and use a gluten sensor to detect whether the meal is actually gluten-free.