- A cancer research arm at the World Health Organization declared for the first time that sweetener aspartame is “possibly carcinogenic” after reviewing “limited evidence,” but a different agency within WHO added that it’s safe to consume the ingredient within a certain limit.
- “While safety is not a major concern at the doses which are commonly used, potential effects have been described that need to be investigated by more and better studies,” Francesco Branca, director of the Department of Nutrition and Food Safety at WHO, said in a statement.
- Aspartame is used in about 6,000 products globally, including soda, chewing gum, confections, gelatins, dessert mixes, puddings and yogurt. Some of the more well-known products using aspartame include Diet Coke, Crystal Light, Extra gum, some Snapple drinks and sugar-free Jell-O.
The decision by the WHO is unlikely to put to bed once and for all the future of the controversial artificial sweetener — a factor that will only be further heightened by conflicting messages coming from the health organization. The U.S. FDA said in a statement that it disagrees with the decision to classify aspartame as a possible carcinogen.
Aspartame, which is about 200 times sweeter than sugar, was approved by the FDA in 1974. Studies for the most part have shown aspartame to be safe. But some have linked it to health risks, further sowing doubt and giving support to aspartame’s critics.
A French study of 100,000 people released in 2022 found those individuals who consumed large amounts of artificial sweeteners such as aspartame had a slightly higher risk of cancer. The sweetener also has been tied to headaches, seizures, migraines, anxiety, depression and insomnia.
The two committees at WHO that released their findings on the risks of aspartame were the Joint Expert Committee on Food Additives and the International Agency for Research on Cancer. JECFA also considered the evidence on cancer risk and concluded that “the evidence of an association between aspartame consumption and cancer in humans is not convincing.”
JECFA’s findings are widely believed to be more relevant for shoppers because it assesses the risk of exposure to a food additive for cancer and other threats, while examining how much daily intake is acceptable. IARC looks at whether a substance could pose a cancer risk.
IARC also only reviews publicly available information, while JECFA also includes non-public proprietary data in its assessment and considers additional outcomes. Health groups, including the FDA, have argued that because of this, IARC’s review of aspartame would be incomplete.
The FDA noted that aspartame is one of the most studied food additives in the human food supply. It also cited shortcomings in the studies on which IARC relied for its review. “FDA scientists do not have safety concerns when aspartame is used under the approved conditions,” the agency said in a statement.
Sweetener and beverage groups applauded the announcement by WHO’s JECFA.
Frances Hunt-Wood, secretary general of the International Sweeteners Association, said in a statement that the JECFA conducted a “thorough, comprehensive and scientifically rigorous review.” He said similar to other low- or no-calorie sweeteners, aspartame, when used as part of a balanced diet, “provides consumers with choice to reduce sugar intake, a critical public health objective.”
Kevin Keane, interim president and CEO of the American Beverage Association, a trade group representing PepsiCo, Coca-Cola and Keurig Dr Pepper, said the “strong conclusion reinforces the position of the FDA and food safety agencies from more than 90 countries.” He added that “people all around the world can be confident in consuming food and beverages with aspartame.”
Still, the possibility that aspartame is dangerous could sow confusion in consumers and push some to consider offerings with alternative sweeteners. JECFA concluded that with a can of diet soft drink containing 200 or 300 mg of aspartame, an adult weighing 70kg (154 pounds) would need to consume more than 9–14 cans per day to exceed the acceptable daily intake.
The findings could prompt food and beverage companies to look for alternative sweetener options that are not dogged by as much criticism or conflicting information. Some companies have already tried. Diet Pepsi used aspartame until 2015 when the company changed the formula. The beverage and snack giant brought the ingredient back a year later following a large decline in sales.
Thomas Galligan, principal scientist with the Center for Science in the Public Interest, said “it’s disturbing, but predictable, to see that the reaction of diet soda makers and the rest of the food industry is to attack IARC, assail the underlying scientific research, and dismiss any concerns about aspartame’s carcinogenicity.”
He added that “more restraint is in order on the industry’s part, and we hope responsible companies will carefully consider IARC’s findings and move away from aspartame.”