Aspartame is commonly used in diet and low calorie food products, including soft drinks and chewing gums. It has been permitted for use in Europe since the 1980s.
Although some studies have suggested possible adverse effects, the European Food Safety Authority (EFSA) has scrutinised their methodology and findings and has repeatedly reaffirmed its view that aspartame is safe. Most recently it said this April, after looking at a study that linked regular intake of the sweetener with increased risk of certain cancers, that it sees no need to alter the acceptable daily intake of 40 mg/kg bw/day.
However anecdotal evidence of ill effects, including headaches and upset stomachs, continues to circulate amongst the general public and online.
In view of this, the FSA is now planning to conduct tests on some individuals who report symptoms in a pilot study that will be used to inform the design and feasibility of a larger study proposed by EFSA.
Andrew Wadge, chief scientist at the FSA, stressed that the agency’s view that aspartame is safe still holds and it is not proposing to test the sweetener’s safety once again.
“However we know that some people consider they react badly to consuming this sweetener so we think it is important to increase our knowledge about what is happening.”
A spokesperson for the agency gave a comparison with peanuts, saying that some people may have a reaction, but that does not mean peanuts are unsafe for the general population.
Part of the study may involve trying to establish a mechanism, or seeing whether the effects that the individuals put down to aspartame could, in fact, have other roots.
The planned study will involve participants being invited on two occasions to consume a specially developed food product that may or may not contain aspartame, in a clinical setting and under medical supervision.
Researchers will then record any symptoms and take a blood sample to measure biochemical parameters.
Industry reaction
However major aspartame producer Ajinomoto has expressed its surprise that the FSA is initiating this study, given its re-confirmation that it has no concerns about the safety.
It said that anecdotal reports linking aspartame to health conditions “include rumours circulated on the internet by scaremongers and conspiracy theorists, mostly from the United States”.
The company cited the position of food safety experts in New Zealand, who said in August 2007 that “the claims being made – and widely reported in the media – are doing a great public disservice”.
However Wadge set out the role he sees for anecdotal evidence in science in his blog on the FSA website yesterday:
“What role does ‘anecdotal evidence’ play in science? Truly anecdotal evidence is not evidence in the scientific sense, it’s observation, it’s often subjective, and the effects seen may be due to a number of factors all varying at the same time. Observation can help us towards understanding certain issues, but is a first step towards a testable hypothesis, not an end in itself.
“Therefore, anecdotal reports do sometimes deserve closer examination, especially when a number of unrelated people are reporting similar things.”
Individuals wanting to find out more or get involved can email aspartame@foodstandards.gsi.gov.uk