The World Health Organization’s cancer agency has deemed the sweetener aspartame — found in diet soda and countless other foods — as a “possible” 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, a special branch of the WHO. The other report was from an expert panel selected by WHO and another UN group, the Food and Agriculture Organization.

The Lyon, France-based cancer agency periodically reviews potential cancer hazards, but doesn’t determine how likely they are to cause cancer in their evaluations which range from “possibly” carcinogenic to “probably” to cancer-causing.

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, though, isn’t changing.

“We’re not advising consumers to stop consuming (aspartame) altogether,” said WHO’s nutrition director Dr. Francesco Branca. “We’re just advising a bit of moderation.”

Aspartame is a low-calorie artificial sweetener that is about 200 times sweeter than sugar. It is a white, odorless powder and the world’s most widely used artificial sweetener.

Aspartame is authorised as a food additive in Europe and the US 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’s in tabletop sweeteners sold as Equal, Sugar Twin and NutraSweet.

Aspartame was approved in 1974 by the US Food and Drug Administration (FDA) 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 “average people are safe to drink up to 14 cans of diet drink a day … and even this ‘acceptable daily limit’ has a large built-in safety factor.”

WHO’s 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 “possibly carcinogenic” on studies in humans and animals that found “limited” 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 “no convincing evidence” 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’t help with weight loss and could lead to increased risk of diabetes, heart disease and early death in adults.