Low-gluten diet linked to an increased risk for Type 2 diabetes, finds study

Got bread? A low gluten diet is linked to a increased risk of Type 2 diabetes, a new study has found.

The Purple Carrot, a meal delivery service in the United States aimed at providing health-conscious meals to folks on-the- go, just launched a new ad campaign featuring one heck of a celebrity tie-in: Tom Brady.

The MVP champ with the five Super Bowl rings and million dollar smile is now shilling his TB12 Performance Meals which he says are designed “for anyone who’s looking to achieve or sustain their own peak performance.” The meals are advertised as high in protein, full of veggies and low in refined sugars. And they’re gluten-free.

Statistics Canada reports that a whopping ten million Canadians are interested in gluten-free products, with “gluten-free” representing the fastest growing food intolerance category, according to Agriculture and Agri-Food Canada. And while an estimated seven per cent of residents are choosing gluten-free diets for medical reasons (one per cent due to celiac disease and another six per cent for gluten sensitivity), a further 22 per cent —seven million Canadians— are classified as gluten avoiders, those who are choosing gluten-free eating because they may have a family member with a gluten-related medical concern or because they believe the choice to be the overall healthier one.

But the belief that gluten-free living is better for everyone is simply not true, say health experts, who insist that there are dangers involved with leaving gluten behind. Essential gut microbes are found in wheat and gluten-based foods help to lower the body’s glycemic index, as well. Further, some of the gluten-free products are not nutritionally equivalent to their gluten-rich relatives, as they often use vitamin-, mineral- and protein-deficient compounds like potato and tapioca starch as gluten substitutes.

Now, a study from Harvard University raises more questions about the gluten-free diet, as researchers have identified an association between low-gluten dietary habits and risk of type 2 diabetes. As presented at a recent meeting of the American Heart Association’s Scientific Sessions, the observational study involved 199,794 people who answered food-frequency questionnaires in the US over two multi-year periods, between 1984 and 1990 and again between 2010 and 2013. Researchers found that study participants who had the highest daily consumption of gluten had a 13 per cent lower risk of developing type 2 diabetes than those who had the lowest daily consumption.

The results speak to the potential health concerns of going gluten-free without a medical need to do so, says Geng Zong, research fellow in the Department of Nutrition at Harvard University.

“Gluten-free foods often have less dietary fibre and other micronutrients, making them less

nutritious and they also tend to cost more,” says Zong. “People without Celiac disease may reconsider limiting their gluten intake for chronic disease prevention, especially for diabetes.”

Yet the study needs to be taken in context, says Sara Chodosh, health reporter for Popular Science, who cautions that the study data did not track those who chose low gluten diets for medical or any other conscious reasons but merely compared individuals with a range of dietary choices. Far from drawing any causal links between low-gluten eating and diabetes, the study’s results can’t say much about why those in the low-gluten cohort had a higher risk of diabetes, says Chodosh.

“Maybe people who ate less gluten in the '80s and '90s also tended to eat worse overall,” he says. “Maybe those people ate not just fewer whole grains, but also more sugar. Maybe gluten has nothing to do with it. We just don’t know yet.”