The independent study by Hull York Medical School said it compared 48 people who claimed to be sensitive to aspartame with 48 control participants with no such sensitivity. Comparing aspartame and placebo bars, the study found there was no difference in participants’ biochemical response to the two types of bar. “Their biochemical markers changed similarly as they should after eating something,” it said.
FSA chief scientific advisor Guy Poppy said: “While the best available evidence shows that aspartame can be consumed safely, a number of individuals have reported adverse reactions after consuming food and drink containing aspartame. Given this anecdotal evidence it was appropriate to see if more could be found out about these reported effects.”
The study’s authors added that they used a “comprehensive battery of psychological tests, biochemistry and state of the art metabonomics”.
They added that it did not evaluate the overall safety of aspartame, “as it is already an approved additive”.
The study was supported by the United Kingdom’s Food Standards Agency.
A ‘gold standard’ study
The study was a double-blind randomised placebo-controlled cross-over study, the gold standard of scientific research.
“[It is] where neither the research team nor the participants know whether the bar consumed contains the test substance or not”, therefore eliminating the risk of prejudgment by participants or researchers which could distort the results, the researchers said.
Dr Thozhukat Satyapalan who conducted the study, said: “We used a variety of state of the art tests …The results of this trial should be reassuring to the public.”
The research paper was peer reviewed by the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) in December 2013. COT concluded that "the results presented did not indicate any need for action to protect the health of the public".
Since aspartame became commonly used by the food and drink industry in the 1980s, it has been the subject of scrutiny.
“Consumer concerns linked aspartame with different types of cancer, multiple sclerosis, blindness, seizures, memory loss, depression, with general concerns regarding both acute and chronic exposure,” said the study.
However, according to international food safety assessment bodies, its safety is well-established. In December 2013, EFSA published an opinion on aspartame following a full risk assessment after “undertaking a rigorous review of all available scientific research on aspartame and its breakdown products”.