The International Agency for Research on Cancer (IARC) and the Joint Committee on Food Additives of the World Health Organization and the International Food and Agriculture Organization (Joint FAO/WHO Expert Committee on Food Additives or JEFCA) announced today, July 14, 2023, the results of their evaluations of the sweetener “aspartame”.

IARC is an independent international cancer research institute and a specialized research body of the World Health Organization established in 1965. It ranks the substances it assesses according to the weight of available scientific evidence as to whether the substance is capable of causing cancer. That is, it characterizes whether a substance is a “hazard”, but it does not calculate the probability of cancer (i.e. it does not examine the “risk”) from human exposure to the substance. JEFCA is an international scientific committee of experts of the World Health Organization and the International Food and Agriculture Organization (which has been meeting since 1956) and carries out a risk assessment (i.e. it considers all possible health effects and potential for harm) taking into account the dietary exposure to substance. IARC and JEFCA have different but complementary roles in the evaluation of chemical substances.

THE EFET clarifies to the consumer the following:

What is aspartame?

Aspartame is a popular synthetic sweetener (about 200 times sweeter than sugar) that is used in a variety of foods and non-alcoholic beverages such as soft drinks, desserts, sweets, chewing gum, yogurts, reduced-calorie products and weight control products, as well as table sweetener. Its presence in food is indicated on food labels either by the name (aspartame) or by the number E 951.

How does the IARC characterize aspartame?

IARC has classified aspartame as a probable carcinogen (category 2B) based on limited evidence (limited evidence) in humans. How does IARC classify the agents/substances it evaluates? IARC ranks the agents/substances it assesses on a 4-level scale according to the weight of available scientific evidence:

Category 1: Human carcinogen. This category includes agents for which there is sufficient evidence to induce carcinogenesis in humans. That is, there is convincing evidence that the agent causes cancer in humans. Evaluation is usually based on results of epidemiologic studies showing the development of cancer in humans exposed to the agent or on sufficient evidence of carcinogenicity in experimental animals accompanied by strong evidence in humans that the agent exhibits one or more of the recognized key features of human carcinogens.

Category 2: Category 2 includes agents for which there is a range of evidence for carcinogenicity in humans and experimental animals. For this reason there are 2 subcategories which indicate different levels of evidence.

Category 2A: Strongly Probable human carcinogen. This category is used when there is “limited evidence of carcinogenicity” in humans accompanied by either sufficient evidence of carcinogenicity in laboratory animals, or by strong mechanistic evidence of the agent showing that the agent exhibits key characteristics carcinogenic to humans. “Limited evidence of carcinogenicity” means that a positive association between exposure to the agent and cancer has been observed, but other causes/explanations for these associations cannot be ruled out. This category also includes agents for which there is insufficient evidence of carcinogenicity in humans but there is sufficient evidence of carcinogenicity in experimental animals as well as strong evidence of the mechanism of action in human cells or tissues.

Category 2B: Possibly carcinogenic to humans. This category includes agents for which there is only one of the following assessments: – Limited evidence of carcinogenicity in humans but also limited or insufficient evidence of carcinogenicity in experimental animals, – Convincing (sufficient) evidence of carcinogenicity in experimental animals but insufficient evidence of carcinogenicity in humans

– Strong mechanism-of-action evidence showing that the agent exhibits one or more key characteristics of human carcinogens. Group 3: Not classifiable as to human carcinogenicity. Agents are included in this category when evidence of carcinogenicity in humans is insufficient, evidence of carcinogenicity in experimental animals is limited or insufficient, and evidence on mechanisms of action is limited or insufficient. Limited evidence of carcinogenicity in experimental animals means that the available information suggests a carcinogenic effect but a definitive conclusion cannot be drawn in experimental animals. IARC Monograph classifications reflect the weight of the body of available scientific evidence as to whether an agent can cause cancer in humans, but do not indicate the degree of cancer risk at a particular level of exposure or by a particular route of exposure. The routes of exposure, the degree of risk and the types of cancer associated with each agent can be very different between different agents. Therefore two agents may be classified as risks in the same category (based on the available scientific evidence) but the hazard (ie, the likelihood of cancer) may differ from one another. As an example, there is a risk that a plane will crash but the degree of risk is extremely low. It is emphasized that IARC does not have the authority to make health-related recommendations. Therefore IARC does not recommend legislation or other public health interventions, which are the responsibility of other international organizations and national bodies. What is the danger of consuming aspartame according to JEFCA? THE JEFCA concluded that there is no convincing evidence from animal or human studies that aspartame has adverse health effects after consumption. This conclusion is supported by the fact that aspartame is metabolized in the intestine to provide three components: aspartic acid, phenylalanine, and methanol. All these substances are naturally absorbed by the body. Aspartame itself does not enter the bloodstream, nor does it accumulate in the body. The three metabolites of aspartame occur naturally in other foods and are used by the body for various functions in exactly the same way. Based on the results of carcinogenicity studies in laboratory animals, the absence of evidence of genotoxicity, and the lack of evidence regarding a mechanism by which oral exposure to aspartame could cause cancer, the panel concluded that it is not possible to establish a relationship between exposure to aspartame in laboratory animals and the occurrence of cancer.

Regarding epidemiological studies, the JEFCA committee concluded that a consistent (clear) association between aspartame consumption and any specific type of cancer has not been demonstrated. All studies had limitations in how exposure (intake) to aspartame was assessed, while other causes such as reverse causality, randomization, errors, and the effect of socioeconomic factors or consumption of other dietary items could explain the observed association. Evaluating all of the above, JEFCA does not change the value of the Acceptable Daily Intake for aspartame, which remains 40 mg/kg of body weight per day.

What is the Acceptable Daily Intake (ADI)

The Acceptable Daily Intake (ADI) is the amount of intake, expressed on a body weight basis, that can be ingested daily throughout life without appreciable risk to health. For aspartame, this price, based on today’s opinion of JEFCA, does not change and remains the same as that of the European Food Safety Authority (EFSA) where has been determined as 40 mg/kg of body weight per day. As an example for a diet soda that contains 200-300 mg of aspartame per can, an adult weighing 70 kg would need to consume 9-14 cans per day, every day to exceed the ADI, since this is of course the sole source of aspartame. The maximum levels at which aspartame can be used, as well as the specific foods to which it can be added, have been established by European legislation, which is automatically incorporated into national legislation (Food and Beverage Code). These levels are set at such values ​​as to ensure that a person consuming a typical diet will not exceed the ADI. For aspartame maximum levels of use in food are set at values ​​that take into account particularly vulnerable populations such as diabetics and children