A study published in the Medical Journal of Australia reported that researchers from the Walter and Eliza Hall Institute in Melbourne found detectable gluten in 2.7% of 256 commonly purchased gluten-free foods, such as crackers, rice snacks, muesli bars, pasta and noodles.
The threshold for ‘gluten free’ labeling by the Codex Alimentarius CODEX (Europe) and the Food and Drug Administration (US) is 20 parts per million (ppm).
Six out of the seven contaminated products had between just under five and 24 ppm (less than half a milligram per standard serve), while one pasta item had 49 ppm (just over 3mg per serve).
Repeat batches in six of the contaminated products – the rice snacks had been recalled by the manufacturer – also contained gluten, indicating the initial results did not reflect isolated episodes.
For a product to be meet the Food Standards Australia New Zealand’s definition of gluten free, it must have no discernible traces of gluten.
Celiac disease affects around one in 70 Australians, however, only one formal analysis (of imported foods) has been published there, according to the study’s authors.
“It’s troubling to think that these foods could be hindering the careful efforts of patients trying their best to avoid gluten,” said Dr Jason Tye-Din, lead author and head of celiac research at the Walter and Eliza Hall Institute and gastroenterology consultant at the Royal Melbourne Hospital.
“For instance, the study found a gluten-free pasta which contained more than 3mg of gluten in a standard single serve. This could have a harmful impact on patients with coeliac disease if consumed frequently.
“Interestingly, many of the items that failed the test were produced in dedicated gluten-free factories, so gluten contamination of externally sourced ingredients may be a factor and should be carefully examined.”
Improvement in practices
Dr Tye-Din said the findings indicated food manufacturers needed to test their products more frequently.
“Even though the vast majority of the products are very safe, there is a signal here that perhaps there could be an improvement in practices.”
Dr Tye-Din added the results had been sent on to the manufacturers, the names of which and the affected products have not been released.
The latest findings follow those found by the same researchers in May that 9% of the 158 samples of “gluten-free” dishes from Melbourne restaurants were not compliant with the Food Standards Australia New Zealand definition of gluten-free.
Celiac disease is a serious autoimmune disorder. The immune system is triggered to attack the bowel after the ingestion of even a small amount of gluten, a protein found in grains such as wheat, spelt and barley. Symptoms vary from person to person, with some experiencing reactions like vomiting, diarrhoea and stomach pain. Over time, inflammation and damage to the small bowel means nutrients cannot be properly absorbed. Cancers, osteoporosis and other severe diseases may develop.
Emma P Halmos, Dean Clarke, Catherine Pizzey and Jason A Tye-Din
Med J Aust, doi: 10.5694/mja18.00457