A popular food colouring, used widely in soda, could raise your risk of cancer, according to a new report.
Public health researchers in the US have analysed soda consumption data in order to understand people’s exposure to a potentially carcinogenic by-product of some types of caramel colour in the US.
Caramel colour is a common ingredient in colas and other dark soft drinks. The results show that between 44 and 58% of people over the age of six typically have at least one can of soda per day, possibly more, potentially exposing them to 4-methylimidazole (4-MEI), a possible human carcinogen formed during the manufacture of some kinds of caramel colour. The results were published online today in PLOS One.
“Soft drink consumers are being exposed to an avoidable and unnecessary cancer risk from an ingredient that is being added to these beverages simply for aesthetic purposes,” says Keeve Nachman, PhD, senior author of the study and director of the Food Production and Public Health Program at the CLF and an assistant professor at the Johns Hopkins Bloomberg School of Public Health.
“This unnecessary exposure poses a threat to public health and raises questions about the continued use of caramel colouring in soda.”
In the UK we down 230 litres per person per year of sodas, the equivalent of around two 300ml cans per person per day. Just over half the sodas we consume are colas.
Building on earlier data
In 2013 and early 2014, Consumer Reports partnered with Johns Hopkins Center for a Livable Future (CLF) to analyse 4-MEI concentrations of 110 soft drink samples purchased from retail stores in California and the New York metropolitan area. This study pairs those results with population beverage consumption data from the National Health and Nutrition Examination Survey (NHANES) in order to estimate the population risks and cancer burden associated with 4-MEI exposures through soda.
While the 2014 study of the 110 samples of soda brands was not large enough to recommend one brand over another or draw conclusions about specific brands, results indicated that levels of 4-MEI could vary substantially across samples, even for the same type of beverage.
“For example, for diet colas, certain samples had higher or more variable levels of the compound, while other samples had very low concentrations,” says Tyler Smith, lead author of the study and a program officer with the CLF.