JOONDALUP, Australia — Gluten-free foods may not be so free of gluten after all, a new study cautions. Researchers in Australia say a common weed, which is actually a popular livestock food source and tennis surface, may be mixing in with crops that specifically avoid this grain protein.
Ryegrass contains a gluten-like protein which could end up with crops such as millet, buckwheat, and sorghum. For people with a gluten intolerance or dealing with celiac disease, study authors say that kind of contamination could lead to bad reactions while eating.
A team from Edith Cowan University and Australia’s national science agency, CSIRO, identified proteins in 10 varieties of ryegrass (Lolium species) which are invasive and commonly spring up in cereal crops. The 19 proteins researchers discovered in ryegrass have similar properties to gluten proteins, which are common in breads, cereals, pastas, and pizzas worldwide.
“We have developed a method to detect these ryegrass proteins that allows us to distinguish them from other grains,” ECU researcher Dr. Sophia Escobar-Correas says in a media release. “While these proteins aren’t strictly defined as gluten, they have the potential to trigger reactions for people who are celiac and those with a gluten intolerance.”
Ryegrass is everywhere, but you may not realize it
Among the many varieties of this grassy weed, farmers actually use several as feed for their livestock. It is native to Europe, Asia, and northern Africa, and has been cultivated and naturalized in both Australia and the Americas.
Along with being yummy grass for cows, ryegrass is also a common turf choice for sports fields — specifically tennis. In fact, ryegrass is the grass of choice for the courts at Wimbledon.
With its prevalence globally in mind, Dr. Escobar-Correas says it’s important to analyze this invasive species and its impact on human health. For people with celiac disease, consuming gluten triggers an immune reaction, creating inflammation which damages the lining of the small intestine. It can also prevent the body from properly absorbing nutrients.
“If these proteins cause a reaction for people with gluten intolerance, then it’s important that we develop tests to detect their presence in food products which are otherwise gluten-free,” Escobar-Correas explains.
“In 2019, the global market for gluten-free foods was worth around $6.3 billion and its growth shows no sign of slowing,” adds ECU Professor Michelle Colgrave.
“This research will help give consumers and producers confidence that products labelled as gluten-free are free from other proteins which may trigger reactions resulting from agricultural co-mingling.”
The findings appear in the journal Frontiers in Nutrition.