Sweetener aspartame is a “possible carcinogen” but it remains safe.
Sweetener aspartame: Two groups associated with the World Health Organisation (WHO) have declared that the artificial sweetener aspartame, while being labeled a
“possible carcinogen,” is still considered safe for consumption at the agreed-upon levels.
These conclusions were reached by separate expert panels—one determining if a substance poses a potential hazard and the other evaluating the actual risk it poses in real-life scenarios.
Aspartame is widely used as a sweetener in various products, including Coca-Cola diet sodas and Mars’ Extra chewing gum.
During a pre-announcement press conference, Francesco Branca, the head of nutrition at the WHO, suggested that consumers should consider neither aspartame nor other sweeteners when making beverage choices.
Instead, he recommended choosing water as an alternative.
The International Agency for Research on Cancer (IARC), based in Lyon, France, made its first statement about aspartame, classifying it as a “possible carcinogen.”
This classification signifies that there is limited evidence linking the substance to cancer.
However, it does not consider the amount of aspartame one would need to consume to be at risk.
The evaluation of consumption levels and associated risks is performed by the WHO and the Food and Agriculture Organization (FAO) Joint Committee on Food Additives (JECFA), located in Geneva.
Following its comprehensive review, JECFA stated that it found no convincing evidence of harm caused by aspartame and recommended that individuals continue to keep their consumption below 40mg/kg per day.
This guideline was initially established by JECFA in 1981 and is also followed by regulators worldwide.
Although some scientists unrelated to the reviews consider the evidence linking aspartame to cancer to be weak, industry associations in the food and beverage sector view these decisions as affirming the safety of aspartame and as a beneficial option for those seeking to reduce sugar intake.
The WHO emphasized that current consumption levels indicate that an individual weighing 60-70kg would need to consume more than 9-14 cans of soda daily to exceed the limit, based on the average aspartame content in these beverages.
This amount is approximately ten times higher than the average consumption of most individuals.
Branca concluded by stating, “Our results do not suggest that occasional consumption would pose a risk to the majority of consumers.”
Reuters first reported in June that the IARC would put aspartame in group 2B as a “possible carcinogen” alongside aloe vera extract and traditional Asian pickled vegetables.
The IARC panel said on Friday it had made its ruling based on three studies in humans in the United States and Europe that indicated a link between hepatocellular carcinoma, a form of liver cancer, and sweetener consumption, the first of which was published in 2016.
It said limited evidence from earlier animal studies was also a factor, although the studies in question are controversial. There was also some limited evidence that aspartame has some chemical properties that are linked to cancer, the IARC said.
“In our view, this is really more a call to the research community to try to better clarify and understand the carcinogenic hazard that may or may not be posed by aspartame consumption,” said Mary Schubauer-Berigan, acting head of the IARC Monographs programme.
Scientists with no links to the WHO reviews said the evidence that aspartame caused cancer was weak.
“Group 2B is a very conservative classification in that almost any evidence of carcinogenicity, however flawed, will put a chemical in that category or above,” said Paul Pharaoh, a cancer epidemiology professor at Cedars Sinai Medical Center in Los Angeles. He said JECFA had concluded there was no “convincing evidence” of harm.
“The general public should not be worried about the risk of cancer associated with a chemical classed as Group 2B by IARC,” Pharaoh said.
Nigel Brockton, vice president of research at the American Institute for Cancer Research, said he anticipates research into aspartame will take the form of large, observational studies that account for any intake in aspartame.
Some doctors expressed concern that the new classification of “possible carcinogen” might sway drinkers of diet soda to switch to caloric sugar beverages.
Therese Bevers, medical director of the Cancer Prevention Center at the University of Texas MD Anderson Cancer Center, in Houston, said “the possibility of weight gain and obesity is a much bigger problem and bigger risk factor than aspartame could ever be.”
The WHO conclusion “once again affirms that aspartame is safe,” said Kate Loatman, executive director of the International Council of Beverage Associations, based in Washington.
“Aspartame, like all low/no calorie sweeteners, when used as part of a balanced diet, provides consumers with choice to reduce sugar intake, a critical public health objective,” said Frances Hunt-Wood, secretary general of the Brussels-based International Sweeteners Association.