LONDON, July 13 (Reuters) – The sweetener aspartame is a “potential carcinogen” but safe to consume at levels already agreed upon, two groups linked to the World Health Organization (WHO) said on Friday.
The judgments are the result of two separate WHO expert panels, one of which flags whether there is any evidence that a substance is a potential risk, and the other of which assesses how much of a real-life risk the substance actually poses.
Aspartame is one of the world’s most popular sweeteners, used in products ranging from Coca-Cola diet sodas to Mars Extra chewing gum.
At a press conference ahead of the announcement, the WHO’s nutrition chief, Francesco Branca, advised consumers weighing drinks not to consider aspartame or sweeteners.
“If consumers are faced with the decision of whether to drink cola sweetened or with sugar, I think they should consider a third option — drinking water instead,” Branca said.
The International Agency for Research on Cancer (IARC), based in Lyon, France, said in its first announcement of the additive early Friday that aspartame is a “probable carcinogen.”
That classification means there is limited evidence that a substance is carcinogenic.
It does not take into account how much a person would need to consume to be at risk, which is considered by a separate committee, the Geneva-based Joint Committee on Food Additives (FAO) (JECFA).
After conducting its own extensive review, JECFA said on Friday it had no conclusive evidence of harm from aspartame and continued to recommend that people keep their consumption below 40mg/kg per day.
JECFA first set this standard in 1981, and regulators worldwide have similar guidelines for their populations.
Several scientists unaffiliated with the criticism said the evidence linking aspartame to cancer was weak. The food and beverage industry associations said the results show that aspartame is safe and a good option for people who want to reduce sugar in their diet.
At current consumption levels, the WHO said a person weighing 60-70kg, for example, would need to drink more than 9-14 cans of soda daily to exceed the limit, based on the average aspartame content in the drinks – about 10 times what most people consume.
“Our results do not indicate that occasional consumption poses a risk to most consumers,” Branca said.
Reuters first reported in June that the IARC would place aspartame in Group 2B as a “possible carcinogen” along with aloe vera extract and traditional Asian pickled vegetables.
The IARC panel made its ruling on Friday based on three studies in humans in the United States and Europe that indicated a link between hepatocellular carcinoma, liver cancer, and consumption of sweets, the first of which was published in 2016.
While the studies in question are controversial, it said limited evidence from previous animal studies is also a factor. There is also some limited evidence that aspartame has certain chemical properties associated with cancer, according to the IARC.
“In our view, this is really a call to the research community to better clarify and understand the cancer risk that may or may not be caused by aspartame consumption,” said Mary Schubauer-Berrigan, executive director of the IARC Monographs Program. .
Scientists unrelated to the WHO review said the evidence that aspartame caused cancer was weak.
“Group 2B is a very conservative classification that puts a chemical in that category or above, regardless of any evidence of carcinogenicity,” says Paul Barrow, M.D., professor of cancer epidemiology at Cedars-Sinai Medical Center in Los Angeles. JECFA concludes that there is no “conclusive evidence” of harm. He said he did.
“The general public should not be concerned about the risk of cancer associated with a chemical classified as Group 2B by IARC,” Barrow said.
Nigel Brockton, vice president of research at the American Institute for Cancer Research, said he expects research on aspartame to take the form of large, observational studies that account for any intake of aspartame.
Some doctors are concerned that the new “potentially carcinogenic” classification could lead diet soda drinkers to switch to calorific sugary drinks.
“Weight gain and obesity are a bigger problem and a bigger risk factor than aspartame,” said Therese Bevers, MD, medical director of the Cancer Prevention Center at the University of Texas MD Anderson Cancer Center in Houston.
The WHO decision “reaffirms that aspartame is safe,” said Kate Lotman, executive director of the Washington-based International Association of Beverages.
“Aspartame, like all low/no-calorie sweeteners, when used as part of a balanced diet, offers consumers the choice to reduce sugar intake, an important public health objective,” said Frances Hunt-Wood, secretary-general of the Brussels-based International. Sweets Society.
Additional reporting by Elisa Welle and Richa Naidu; Editing by Caroline Hummer, Catherine Evans and Leslie Adler
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