Gluten-Free Diet Could Increase Type 2 Diabetes Risk, Study Suggests

Gluten-free foods are 'less nutritious and also tend to cost more'.
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People who deliberately cut gluten from their diets could be increasing their risk of Type 2 diabetes, according to research.

A new study found that people who consumed very low amounts of gluten had a higher risk of developing Type 2 diabetes than those who consumed higher amounts of it.

While some people have to cut gluten from their diets for medical reasons such as coeliac disease or intolerance, others voluntarily go gluten-free - and it’s this group of people who may be unnecessarily damaging their health.

“People without coeliac disease may reconsider limiting their gluten intake for chronic disease prevention, especially for diabetes,” said Geng Zong, a research fellow at Harvard University.

Gluten is a protein found in wheat, rye and barley, which gives bread and other baked goods elasticity during the baking process and a chewy texture in finished products.

A small percentage of people cannot tolerate gluten due to coeliac disease or gluten sensitivity, yet gluten-free diets have also become increasingly popular for people without these conditions.

“We wanted to determine if gluten consumption will affect health in people with no apparent medical reasons to avoid gluten,” said Geng Zong.

“Gluten-free foods often have less dietary fibre and other micronutrients (dietary components such as vitamins and minerals), making them less nutritious and they also tend to cost more.”

In the long-term study, involving almost 200,000 people, most participants had a gluten intake below 12 grams per day. Within this range, those who ate the most gluten had a lower Type 2 diabetes risk during 30 years of follow-up.

Study participants who ate less gluten also tended to eat less cereal fibre, a known protective factor for Type 2 diabetes development.

After further accounting for the potential effect of cereal fibre, people who consumed the most gluten had a 13% lower risk of developing Type 2 diabetes in comparison to those with the lowest daily gluten consumption.

It’s worth noting that most of the participants took part in the study before gluten-free diets became popular, so more research is needed to look into the effects on gluten abstainers.

Nutritionist Charlotte Stirling-Reed advises people to steer clear of gluten-free diets if they don’t have a medical condition that requires them to do so.

“It’s important to remember that going gluten free is only necessary if you have coeliacs disease, otherwise you may simply be unnecessarily restricting yourself,” she said.

“If you do go gluten-free, make sure you’re opting for variety everyday and ensure you don’t over rely on processed gluten free products.”