The EFSA ANS Panel provides a scientific opinion on the safety of aspartame (E 951). Aspartame is a sweetener authorised as a food additive in the EU. In previous evaluations by JECFA and the SCF, an ADI of 40 mg/kg bw/day was established based on chronic toxicity in animals. Original reports, previous evaluations, additional literature and data made available following a public call were evaluated. Aspartame is rapidly and completely hydrolysed in the gastrointestinal tract to phenylalanine, aspartic acid and methanol. Chronic and developmental toxicities were relevant endpoints in the animal database. From chronic toxicity studies in animals, a NOAEL of 4000 mg/kg bw/day was identified. The possibility of developmental toxicity occurring at lower doses than 4000 mg/kg in animals could not be excluded. Based on MoA and weight-of-evidence analysis, the Panel concluded that developmental toxicity in animals was attributable to phenylalanine. Phenylalanine at high plasma levels is known to cause developmental toxicity in humans. The Panel concluded that human data on developmental toxicity were more appropriate for the risk assessment. Concentration-response modelling was used to determine the effects of aspartame administration on plasma phenylalanine using human data after phenylalanine administration to normal, PKU heterozygote or PKU homozygote individuals. In normal and PKU heterozygotes, aspartame intakes up to the ADI of 40 mg/kg bw/day, in addition to dietary phenylalanine, would not lead to peak plasma phenylalanine concentrations above the current clinical guideline for the prevention of adverse effects in fetuses. The Panel concluded that aspartame was not of safety concern at the current aspartame exposure estimates or at the ADI of 40 mg/kg bw/day. Therefore, there was no reason to revise the ADI of aspartame. Current exposures to aspartame – and its degradation product DKP – were below their respective ADIs. The ADI is not applicable to PKU patients.
EFSA full risk assessment on aspartame in 2013 represents one of the most comprehensive risk assessments of aspartame ever undertaken and concludes that aspartame is safe at current levels of exposure. To carry out its risk assessment, EFSA has undertaken a rigorous review of all available scientific research on aspartame and its breakdown products, including both animal and human studies.
Experts of EFSA’s ANS Panel have considered all available information and, following a detailed analysis, have concluded that aspartame and its breakdown products are safe for human consumption at current levels of exposure and that the current Acceptable Daily Intake (ADI) of 40mg/kg bw/day is protective for the general population. However, in patients suffering from the medical condition phenylketonuria (PKU), the ADI is not applicable, as they require strict adherence to a diet low in phenylalanine (an amino acid found in proteins).
Following a thorough review of evidence provided both by animal and human studies, experts have ruled out a potential risk of aspartame causing damage to genes and inducing cancer. EFSA’s experts also concluded that aspartame does not harm the brain, the nervous system or affect behaviour or cognitive function in children or adults. With respect to pregnancy, the Panel noted that there was no risk to the developing fetus from exposure to phenylalanine derived from aspartame at the current ADI (with the exception of women suffering from PKU).