In 2011 and 2013, EFSA, the European Food Safety Authority, updated its
Opinion on the basis of the most recent studies on aspartame including the
assessment of all unpublished studies.
What is aspartame?
Aspartame (E 951) is a dipeptide of
methyl ester and
L-aspartic acid, two
amino acids which are natural
components of proteins. It is used as an
artificial sweetener authorised as a food additive in the EU. Once ingested,
aspartame is rapidly and completely hydrolysed in the
gastrointestinal tract to its
degradation products, which are
mainly phenylalanine and aspartic acid, but also
diketopiperazine (DKP) and
What is phenylketonuria?
Some humans show a slightly reduced capacity to eliminate
phenylalanine compared to normal
individuals but some (the so-called
phenylketonuria (PKU) patients) have a
markedly reduced capacity for phenylalanine elimination. Phenylketonuric mothers
with poorly controlled phenylalanine intake in their diet during pregnancy may
give birth to babies with congenital heart diseases, microcephaly and impaired
neurological function. If the
phenylalanine intake via the diet is not strictly controlled phenylcetonuric
babies show severe impairment in
This is why it is recommended to persons suffering from
phenylketonuria to not consume
aspartame and to limit as much as possible their exposure to
phenylalanine, which is naturally
present in the regular diet. Most of the food items in which aspartame is
authorised are subject to limitations.
Were the EFSA conclusions modified after the risk reevaluation of aspartame?
The EFSA confirmed that aspartame consumption was not a safety concern at the
current exposure estimates, which are below the Acceptable Daily Intake (ADI)
recommended in 2006 of 40 mg/kg body weight/day .
What about the results of the carcinogenicity studies not considered in the previous evaluation?
No new data demonstrated a genotoxic or
carcinogenic potential of
aspartame; in particular the results of a
carcinogenicity study on aspartame
conducted in mice in 2010, did not provide a sufficient basis to reconsider the
previous evaluations on aspartame.
The expert committee also noted there was no
epidemiological evidence for possible
associations between aspartame consumption and various types of
cancers in the human
Are there risks of developmental effects on the foetus or premature delivery linked to aspartame?
Many experimental studies were conducted on the potential
toxicity of aspartame on
development. High levels of
phenylalanine in the blood is known
to cause problems with development, but when the phenylalanine originating from
aspartame consumption is added to the phenylalanine from the diet, it was
calculated that exposure is still too low to cause such effects. For the risk of
premature delivery, there is no evidence from
epidemiological studies to support a
causal relationship, however, additional studies are required to definitively
conclude about such possible association.