FILE PHOTO: A bottle of soda is photographed in Washington Thursday, January 23, 2014. On Thursday, July 13, 2023, the International Agency for Research on Cancer, the cancer research arm of the World Health Organization, deemed aspartame, the world鈥檚 most widely used artificial sweetener, to be 鈥減ossibly carcinogenic鈥� to humans. Separately, a United Nations expert group assessing the same evidence said their guidance regarding safe consumption of the sweetener remained unchanged. (AP Photo/J. David Ake, File)
The World Health Organization鈥檚 (WHO) cancer agency has deemed the sweetener aspartame 鈥� found in diet soda and countless other foods 鈥� as a 鈥減ossible鈥� cause of cancer, while a separate expert group looking at the same evidence said it still considers the sugar substitute safe in limited quantities.
The differing results of the coordinated reviews were released early Friday. One came from the International Agency for Research on Cancer (IARC), a special branch of the WHO. The other report was from an expert panel selected by WHO and another United Nations group, the Food and Agriculture Organization.
The Lyon, France-based cancer agency periodically reviews potential cancer hazards, but doesn鈥檛 determine how likely they are to cause cancer in their evaluations which range from 鈥減ossibly鈥� carcinogenic to 鈥減robably鈥� to cancer-causing.
READ: Aspartame set to be declared possible carcinogen
Aspartame joins a category with more than 300 other possible cancer-causing agents, including things like aloe vera extract, Asian-style pickled vegetables, and carpentry work.
The guidance on use of the sweetener, however, isn鈥檛 changing.
鈥淲e鈥檙e not advising consumers to stop consuming (aspartame) altogether,鈥� said WHO鈥檚 nutrition director Dr. Francesco Branca. 鈥淲e鈥檙e just advising a bit of moderation.鈥�
Here鈥檚 a look at the announcement:
What is aspartame?
Aspartame is a low-calorie artificial sweetener that is about 200 times sweeter than sugar. It is a white, odorless powder and the world鈥檚 most widely used artificial sweetener.
READ: WHO warns against using artificial sweeteners
Aspartame is authorized as a food additive in Europe and the United States and is used in numerous foods, drinks such as Diet Coke, desserts, chewing gum, medications including cough drops and foods intended to help with weight loss. It鈥檚 in tabletop sweeteners sold as Equal, Sugar Twin, and NutraSweet.
Aspartame was approved in 1974 by the US Food and Drug Administration with an acceptable daily intake of 50 milligrams per kilogram of body weight. According to the FDA, a person weighing 132 pounds (60 kilograms) would need to consume about 75 aspartame packets to reach that level.
UN experts evaluated the safety of aspartame in 1981 and set the safe daily limit slightly lower, at 40 milligrams of aspartame per kilogram.
David Spiegelhalter, an emeritus statistics professor at Cambridge University, said the guidance means that 鈥渁verage people are safe to drink up to 14 cans of diet drink a day 鈥� and even this 鈥榓cceptable daily limit鈥� has a large built-in safety factor.鈥�
READ: MSG, aspartame safe additives, says FDA, quoting int鈥檒 agencies
What did the two groups say?
WHO鈥檚 cancer agency, IARC, convened its expert group in June to assess the potential of aspartame to cause cancer. It based its conclusion that aspartame is 鈥減ossibly carcinogenic鈥� on studies in humans and animals that found 鈥渓imited鈥� evidence that the compound may be linked to liver cancer.
In a separate evaluation, experts assembled by WHO and the food agency updated their risk assessment, including reviewing the acceptable daily intake. They concluded there was 鈥渘o convincing evidence鈥� at the currently consumed levels that aspartame is dangerous; their guidelines regarding acceptable levels of consumption were unchanged.
The move comes weeks after the WHO said that non-sugar sweeteners don鈥檛 help with weight loss and could lead to increased risk of diabetes, heart disease, and early death in adults.
READ:
Should I be concerned about getting too much?
Not as long as you don鈥檛 exceed the guidelines. The FDA said scientific evidence continues to support the agency鈥檚 conclusion that aspartame is 鈥渟afe for the general population,鈥� when used within limits.
Almost any substance can be dangerous in excessive amounts, said David Klurfeld, a nutrition expert at the Indiana University School of Public Health-Bloomington.
鈥淭he dose makes the poison,鈥� said Klurfeld, who previously served on an IARC panel. 鈥淓ven essential nutrients like vitamin A, iron and water will kill you within hours if too much is consumed.鈥�
So what should consumers do?
WHO鈥檚 Branca said it was acceptable for people to consume a 鈥減retty large鈥� amount of aspartame without suffering any ill effects. 鈥淗igh consumers鈥� might want to cut back, he said.
Dr. Peter Lurie, executive director of the Center for Science in the Public Interest, which previously nominated aspartame for IARC review, said there鈥檚 an easy choice for consumers.
鈥淎t least when it comes to beverages, our message is your best choice is to drink water or an unsweetened beverage,鈥� he said.
Most people, though, probably don鈥檛 pay much attention to IARC evaluations. The agency has previously classified processed meat like hot dogs and bacon as cancer-causing, noting in particular its link to colon cancer. That move surprised even others in the scientific community 鈥� the United Kingdom鈥檚 biggest cancer charity reassured Britons that eating a bacon sandwich every so often wouldn鈥檛 do them much harm.
What does this mean for the food and beverage industry?
Food and beverage producers say there鈥檚 no reason to avoid products with aspartame.
鈥淭here is a broad consensus in the scientific and regulatory community that aspartame is safe,鈥� the American Beverage Association said in a statement.
WHO鈥檚 Branca said the agency advises food manufacturers in general to 鈥渦se ingredients that do not require the addition of too much sugar.鈥� After the latest assessments of aspartame, Branca said that using sweeteners 鈥渋s probably not the way forward.鈥�