The sweetener aspartame, one of the most used in the food industry, has been classified as "possibly carcinogenic to humans" by the World Health Organization (WHO). But the WHO itself warns that aspartame is safe in the doses at which it is usually consumed.
Liver cancer is the only type of tumor in which there are epidemiological studies that suggest that aspartame could cause it, says the WHO. Studies with rats and mice, on the other hand, have linked high doses of the sweetener to other types of cancer, such as some of the lung, breast and kidney.
"It is acceptable to consume products with aspartame", Francesco Branca, director of the Department of Nutrition and Food Safety of the WHO, declared in a press conference on Wednesday. "We are reassured that an occasional level of exposure is safe." But, after declaring aspartame as a possible carcinogen, the WHO makes the following recommendations.
To citizens: "We certainly recommend consumers to limit the consumption of sweeteners" and not to replace them with sugar, Branca declared.
To governments: "The WHO does not recommend that the authorities withdraw products from the market", he added.
In the food industry: “Companies should reconsider their products; we know that many sweeteners have risks; it's about looking for tasty products without sweeteners”.
And to the scientific community: "a call is made to try to clarify the risk posed by aspartame", Mary Schubauer-Berigan, of the International Agency for Research on Cancer (IARC), declared at the press conference ), which is part of the WHO.
The evaluation of aspartame has been carried out by two groups of experts who have worked separately. On the one hand, 25 scientists from 12 countries convened by the IARC have reviewed the scientific evidence to assess whether the sweetener is carcinogenic or not, regardless of the dose at which it is taken. On the other hand, the Committee of Experts on Food Additives of the WHO and the FAO has evaluated the amounts at which aspartame could pose a risk.
The IARC working group has evaluated epidemiological studies of people who consume aspartame frequently, as well as animal and cell culture studies to understand how the sweetener can affect different organs and tissues.
According to the results presented in The Lancet Oncology, in which they present their conclusions today, "aspartame induced oxidative stress in several tissues, including the liver, in multiple rodent studies." In addition, "it induced chronic inflammation".
A study based on data from almost half a million people in ten European countries found in 2016 more cases of liver cancer in people who consumed soft drinks with aspartame than in people who did not. Two other studies conducted in the US published last year observed the same correlation. But none of the three proved that aspartame was the cause of liver cancers.
The classification of the sweetener as a possible carcinogen "should not be interpreted as a statement that there is a known risk of cancer from the consumption of aspartame", clarified Schubauer-Berigan.
The expert committee on food additives, for its part, has concluded that "there is no convincing evidence of risk for people below the daily limit of 40 milligrams of aspartame per kilogram of body weight", which is the maximum level considered acceptable by the European Food Safety Authority (EFSA). A 60-pound person would have to drink 12 cans of aspartame-sweetened soda a day to reach that amount.
The possible health risk of aspartame "is not something we can rule out at this point," especially for people who consume it in high amounts, Francesco Branca said. "There is only one very obvious recommendation: reduce consumption."
For children and adolescents, the director of the Department of Nutrition and Food Safety of the WHO emphasized that "having a high consumption of soft drinks, and getting used to their taste from an early age, is not a good practice" .
