Gluten intolerance can partly be overcome by swallowing an enzyme pill with food, research has shown.
The simple measure can allow people sensitive to the wheat protein to consume small quantities of gluten without experiencing bloating, diarrhoea and abdominal pain.
Scientists say the discovery could be a "game-changer" for gluten-intolerant individuals who have to be super-careful about what they eat.
Lead researcher Dr Julia Konig, from the University of Orebro in Sweden, said: "Since even small amounts of gluten can affect gluten-sensitive patients, this supplement can play an important role in addressing the residual gluten that is often the cause of uncomfortable symptoms.
"Studies show that even when following a gluten-free diet, unintentional gluten intake can still occur, depending on how strict a gluten-free dieter is."
For the study, 18 gluten-sensitive volunteers were given a porridge made with two crumbled wheat biscuits containing gluten. They also took high or low doses of the enzyme AN-PEP, or a "dummy" placebo pill.
Both doses of the enzyme were found to break down gluten in the stomach and small intestine. Gluten levels in the stomach were 85% lower in participants who swallowed the enzyme than in those given the placebo.
Compared with the placebo, taking the enzyme lowered gluten levels by up to 87% once food had reached the duodenum, the first part of the small intestine.
The findings were presented to experts attending the Digestive Disease Week 2017 meeting in Chicago.
Dr Konig added: "This substance allows gluten-sensitive patients to feel safer, for example, when they are out with friends at a restaurant and can't be sure whether something is 100% gluten-free.
"Since even small amounts of gluten can affect gluten-sensitive patients, this supplement can play an important role in addressing the residual gluten that is often the cause of uncomfortable symptoms.
"Our results suggest that this enzyme can potentially reduce the side effects that occur when gluten-sensitive individuals accidentally eat a little gluten. We are not suggesting that AN-PEP will give these individuals the ability to eat pizza or pasta, sources of large amounts of gluten, but it might make them feel better if they mistakenly ingest gluten."
She stressed that the enzyme was not tested on coeliac disease patients, who can be seriously harmed by even small amounts of gluten. Coeliac patients should not consume any gluten, even with the enzyme, Dr Konig warned.