Aspartame (almost) cleared

The aspartame molecule

The aspartame molecule (Illustration: Wikimedia)

The artificial sweetener aspartame has been associated with some controversy from its initial approval for use in dry food in 1974 by the Food and Drug Administration in the USA. Aspartame has since been deemed safe for human consumption by over 100 regulatory agencies in their respective countries. Although there were some clear irregularities in the initial submission by G.D. Searle, this was not considered detrimental to its approval.

Because of the initial controversy, the safety of aspartame has been studied extensively since its discovery with research that includes animal studies, clinical and epidemiological research, and post-market surveillance. Aspartame is now one of the most rigorously tested food ingredients to date. Comprehensive peer-review studies, as well as independent scrutiny by governmental regulatory bodies, have analysed the published research and deemed aspartame safe for consumption at current levels. This has not silenced the critics.

The ultimate review?

In May, 2011, the European Food Safety Authority (EFSA) was asked by the European Commission to bring forward a full re-evaluation of the safety of aspartame, previously planned for completion by 2020. On January 8, 2013, EFSA released a draft opinion for comment. As part of the evaluation process, EFSA commissioned an external review of the available literature on aspartame. This review was published on 1 March, 2013 and provides an overview of current knowledge regarding the metabolism and toxicity of aspartame. From a database containing 5,023 references the review team identified 1,366 documents of direct or indirect relevance to the risk assessment of aspartame. After scrutiny of those documents, 358 were carried forward for detailed examination.

Review and consultations on aspartame (Photo: ALDEADLE)

Aspartame under review (Photo: ALDEADLE)

The review team noted that aspartame after ingestion is immediately split into three constituents already in the gastrointestinal system and these are consequently absorbed individually. Two of the three components (aspartate and methanol) are cleared rapidly from the body and the only component remaining in the circulation system is phenylalanine. Aspartame itself is normally not absorbed.

The effective potential toxicity of aspartame is therefore only related to the phenylalanine component.

The team reported that:

  • No significant acute or subchronic toxicity had been observed in animal models or in humans even at the highest doses of aspartame which could reasonably be administered, and early concerns that aspartame might cause neurotoxicity in neonates and infants could not be substantiated.
  • There was no evidence to indicate that aspartame is genotoxic. Reported marginally positive results occurred only sporadically and did not indicate any particular cause for concern.
  • Available chronic toxicity studies did not indicate any overt carcinogenic effect in experimental animals due to aspartame, but all the conventional studies were limited in various ways.
  • One epidemiological study addressing possible reproductive effects in humans found an increased risk of preterm delivery in women who frequently consumed either carbonated or (to a lesser extent) non-carbonated diet drinks but did not address aspartame directly and was subject to a number of confounding factors.

The review concluded that there was no consistent evidence that aspartame has adverse effects, either in healthy individuals or in potentially susceptible groups, under normal conditions of use although phenylketonurics do need to regulate their intake of aspartame for health reasons. They are supported in doing this by clear labelling of aspartame-containing products. The review team left some question marks in relation to chronic and reproductive toxicity and supported further research to conclusively exclude any such effects.

Current state of the art

EFSA’s draft opinion now states that aspartame and its metabolites “pose no toxicity concern for consumers at current levels of exposure. The current Acceptable Daily Intake (ADI) is considered to be safe for the general population and consumer exposure to aspartame is below this ADI”. The final opinion is expected to be delivered in May 2013.

If this will be the end of the controversy over the use of aspartame as a food additive is still doubtful. The remaining uncertainty over chronic and reproductive toxicity, although slight, might need to be conclusively resolved to silence all critics. Further unnecessary controversy has been ignited by the dairy industry request to sweeten flavoured milk for children with aspartame without declaring it on the label.

Related articles

3 thoughts on “Aspartame (almost) cleared

  1. Thank You for your support and the link. The F.D.A. has ruled that GMOs are safe as well. They are run by Monsanto. How can we the people trust them? If Aspartame is so safe why not include it on the labels of the products. Now they want to inject it into milk with no labeling. Something is just not right with this picture. Thank you again for including us

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s