A popular sugar additive is fuelling superbug outbreaks, according to scientists.
Trehalose, which is found in a range of products from biscuits to noodles, is metabolised by the killer bacteria Clostridium difficile (C. diff), an infection that attacks the bowels and can be fatal.
Research published in the journal Nature claims that increased use of trehalose – claimed by some to be a "healthy" sugar alternative – has sparked health crises around the world.
Popular supermarket products that list trehalose as an ingredient include Fox's Party Rings, Tostito's Tortilla Snacks and Grace's Original Aloe Vera Drink. All three manufacturers have been contacted for comment.
Until now, antibiotics have thought to be largely to blame for upsetting the balance of the bowel, causing the C. diff to multiply and produce toxins that make a person ill.
But scientists found that two C. diff strains that have caused major outbreaks – RT027 and RT078 – break down trehalose and thrive off it.
"This study provides a good example of how changes in human activity (e.g. changes in food additives) can have unintended consequences relating to the emergence and ultimately the global spread of an infectious agent," Professor Brendan Wren told the Daily Mail.
C. diff bacteria are found in the digestive system of about 1 in every 30 healthy adults. They often coexist harmlessly with other bacteria in the stomach.
Outbreaks are most common on hospital wards – C. diff is one of a number of modern, antibiotic resistant superbugs to emerge in recent years.
Half a million Americans were diagnosed with the bug in 2011 – and 29,000 of those people infected died within 30 days of diagnosis.
NHS Choices claims that people who contract C. diff may need to come off or change their antibiotics. In rare cases, it warns that part of the bowel may need to be removed to stop the spread of the infection.
The connection between C. diff and the overuse of antibiotics has long been established. However, the new research suggests that fuel for the infection could be much closer to our dinner tables.
Jimmy D. Ballard of the University of Oklahoma Health Sciences Center described the findings as "compelling", in conversation with the LA Times.
"It is impossible to know all the details of events surrounding the recent C. difficile epidemics, but the circumstantial and experimental evidence points to trehalose as an unexpected culprit," he added.
Trehalose is a naturally-occurring sugar that occurs in plants and insects, which consists of two glucose molecules bound together.
As well as being used in cakes, preserves and juices, it is also added to snack bars, frozen foods, instant noodles and some chocolates.
Researchers were also fascinated to discover that the two distinct strains of C. diff independently acquired different methods to metabolise trehalose.