Health authorities should consider banning the widely used artificial sweetener aspartame, after the World Health Organisation concluded there is “limited evidence” it may cause cancer, says a leading expert.
Others called for more studies to clear up longstanding speculation that the food additive, added to thousands of products, including fizzy diet drinks, medicines, chewing gum, and sweets, is a possible cancer-causing chemical in humans.
Last week the WHO International Agency for Research on Cancer published a report concluding the popular ingredient might be linked to human cancers. It found “limited evidence” aspartame may cause liver cancer.
The news came on the same day (14 JULY) that another WHO body, the UN Food and Agriculture Organisations Joint Expert Committee on Food Additives (JECFA) published a separate analysis stating patterns of aspartame consumption can safely continue.
It concluded the sweetener is generally safe up until very large doses.
The seemingly contradictory findings stem from the two groups’ differing remits. The IARC, which found that aspartame was possibly linked to cancer, studies whether a substance has the potential to cause harm. The second group, JECFA, aims to estimate the actual risk that such harms will actually occur.
However, Erik Millstone, Professor of Science Policy in the University of Sussex Business School, believes there is enough evidence about the possible dangers of the sugar substitute, to ban it.
Professor Millstone, a leading European expert on aspartame, who has been researching into and publishing analyses of the product for over thirty years said: “The safety and/or toxicity of aspartame is relevant because the sweetener is very widely consumed in so-called ‘diet’ drinks, and in thousands of other food and drink products.
There have been many studies into its safety and it is clear to me that aspartame has been shown to cause cancer in mice and rats in doses lower or the same as the corresponding dose in humans.
There are now good reasons for thinking that this product might be cancer-causing in humans and this is unacceptable. There are good reasons for saying aspartame should no longer be permitted.”
He added: “I have examined many studies into this and often studies which are unfavourable to aspartame are wrongly discarded as being poor quality while those which are favourable are not critically assessed. Regulators are not protecting consumers.
“They are protecting the interests of the junk food industry. People should not have to get cancer before we ban this product. What does the barrier have to be before we take steps to protect public health?”
Other experts said more evidence was needed before any ban could be considered. Prof Kevin McConway, Emeritus Professor of Applied Statistics, Open University, said: “IARC, and JECFA in its assessment (which is based on risk), both comment on the existence of bias, flaws and inconsistencies in the available evidence.
More and better evidence will, I hope, become available in the future, and this could well lead one or both organisations to revisit their assessments.
But, since that evidence does not yet exist, we can’t say what direction any reassessment might go in….This uncertainty is uncomfortable, perhaps, but it’s not going to go away, at least until more and better research is done.”
Prof Robin May, Chief Scientific Adviser of, the Food Standards Agency (FSA), said: “We welcome the WHO’s call for more and better studies to help increase understanding of this potential issue.”
Prof Andy Smith, from the toxicology unit at the University of Cambridge, said:
“For the first time, IARC has evaluated the possibility that aspartame might cause cancer in humans i.e. whether it can be viewed as a cancer hazard…The Joint Expert Committee saw no new reasons to change its longstanding recommendation of an acceptable daily intake 0-40 mg per kg of body weight without appreciable health risk.
“Overall, the IARC and JECFA reports should not be a source of great concern. They have called for any future animal and human studies to be conducted under strict modern guidelines to encourage both scientific and public confidence.”