Possibly carcinogenic: WHO on artificial sweetener aspartame

Aditi Tandon

New Delhi, July 14

The World Health Organisation’s cancer research arm on Friday classified artificial sweetener aspartame, widely used in foods and beverages like diet cokes, as possibly carcinogenic, citing “limited evidence” for its carcinogenicity (potential to cause cancer) in humans.

Used in food, drinks

Aspartame widely used since the 1980s in foods and beverages, including diet drinks, chewing gum, gelatin, ice cream, yogurt, breakfast cereal, toothpaste and medications such as cough drops and chewable vitamins

The WHO’s International Agency for Research on Cancer (IARC) and the Food and Agriculture Organisation (FAO)’s Joint Expert Committee on Food Additives (JECFA) kept current daily recommended dosages of aspartame in foods and drinks unchanged at 40 mg per kg of body weight saying proof of the product causing cancer in humans was limited and moderate intake was safe. The IARC has four levels of classification to rate cancer causing products—Group-1: definitely carcinogenic with sufficient evidence of cancer in humans; Group-2A: probably carcinogenic with limited evidence of cancer in humans, but sufficient evidence in experimental animals; Group-2B: possibly carcinogenic with limited evidence of cancer in humans and less than sufficient evidence in animals; and Group-3: not classifiable for cancer.

How much is risky

A 70-kg adult would need to consume over 9–14 diet soft drink cans (containing 200 or 300 mg of aspartame) to exceed acceptable daily intake, assuming no intake from other food sources

Aspartame has been placed in Group-2B category alongside gasoline engine exhaust, occupational exposure as hairdressers or barbers and lead. Group-1 includes tobacco smoking, solar radiation, alcoholic beverages and ionising radiation. Group-2A features emissions from high temperature frying, DDT, consumption of red meat and night shift work. Simply put, consumers with moderate intake of diet cokes and other aspartame-containing products needn’t worry. “Data evaluated indicates no sufficient reason to change the previously established acceptable daily intake (ADI) of 0–40 mg/kg body weight for aspartame and it is safe to consume within this limit per day,” the IARC said.

With a can of diet soft drink containing 200 or 300 mg of aspartame, an adult weighing 70kg would need to consume more than 9–14 cans per day to exceed the acceptable daily intake, assuming no other intake from other food sources. Aspartame was named “possibly carcinogenic” based on limited evidence for cancer in humans (specifically for hepatocellular carcinoma, a type of liver cancer) and limited (but not sufficient) evidence for cancer in experimental animals. “The findings of limited evidence of carcinogenicity in humans and animals underscore the need for more research,” said Mary Schubauer-Berigan of the IARC.