Why does the gluten-free diet fail some coeliac disease sufferers?

Around 80% of Australian coeliac disease sufferers do not know they have the autoimmune disease. They just accept chronic tiredness, anaemia, bloating, abdominal pain, diarrhoea and other gastric symptoms as a part of life.

Coeliac disease is fairly common, with around one in 60 women and one in 80 men in Australia affected. The disease is caused by an abnormal immune system response to the protein gluten, which is present in wheat, rye, barley and oats. A strict, lifelong gluten-free diet is currently the only recognised medical treatment.

By removing the cause of the disease, a gluten-free diet allows the small bowel lining to heal and symptoms to resolve. As long as the gluten-free diet is strictly adhered to, problems arising from coeliac disease should not return. However, for about 50% of Australians, coeliac disease symptoms and signs of intestinal damage persist even after years of following a gluten-free diet.

Coeliac Australia is now funding two research programs at the Walter and Eliza Hall Institute of Medical Research.

Gastroenterologist Dr Jason Tye-Din will lead the study looking at the safety of oats for people with coeliac disease.  Only some coeliacs get sick when eating oats, yet all coeliac patients are encouraged to exclude them from their diet. Why? Is there a safe dose of oats below which patients will not incur symptoms? What part of the oat causes problems for coeliacs? These are the questions Dr Tye-Din’s team is hoping to answer.

The other WEHI study will investigate why half of all Australian adults with coeliac disease fail to get full healing of their bowel or suffer symptoms even after many years on a gluten-free diet.

Some of the reasons being explored to explain the failure of the gluten-free diet include:

• Packaged food labelled as gluten-free actually containing gluten
• Food handling practices in food outlets that prepare and sell gluten-free foods
• Patient knowledge of and compliance with the gluten-free diet
• The accuracy of tests intended to measure gluten levels in food

“The cause of ongoing intestinal inflammation or symptoms in people with coeliac disease is often attributed to accidental or low amounts of gluten exposure, but why this happens and what causes it is poorly understood,” said specialist dietitian Dr Emma Halmos. “Persistent intestinal inflammation due to inadequately treated coeliac disease is a major concern, as it substantially increases the risk of complications such as other autoimmune diseases, osteoporosis, cancer and death.”

People with coeliac disease interested in participating in either study should contact the Walter and Eliza Hall Institute’s coeliac research nurse, Cathy Pizzey, via coeliac@wehi.edu.au.

Image credit: ©stock.adobe.com/au/djvstock