Research Update

Expert Panel Affirms Aspartame Safety

September 2007 - A thorough review of the existing of science related to the safety of aspartame by eight of the world's leading toxicologists has concluded that aspartame is safe even at the highest level of current consumption and that suggestions of adverse effects, including those raised by rat studies in Italy, have 'no credible scientific basis.'

Published in the September 2007 issue of Critical Reviews in Toxicology, the expert review covered more than 500 studies, articles and reports from the past 25 years, including work that was submitted to government bodies as part of the regulatory approvals process but never published, to assess aspartame's potential effect on behavior, reproductive health, neurological function, cancer, and tumor development. The reviewed studies also covered a broad range of population subgroups, including people with Parkinson's disease and diabetes, children with various sensitivities, people with allergies and those suffering from depression.

To address changing consumption patterns increased use of aspartame in foods and beverages over the past 30 years, the reviewers also estimated current consumption levels of aspartame using the most recent US food consumption survey data available, and assumptions that most likely overestimated aspartame consumption. They determined the average intake of aspartame to be 4.9 mg/kg of body weight, was far below the upper-limit of 50 mg/kg per day established by the US FDA. The reviewers concluded: "The weight of existing evidence shows that aspartame is safe at current levels of consumption? No credible evidence was found that aspartame is carcinogenic, neurotoxic, or has any other adverse effect on health when consumed even at quantities many times the established ADI [acceptable daily intake] levels."

The review also evaluated and found 'numerous flaws' in two recent studies conducted by the Ramazzini group in Italy that claimed to find a link between aspartame and cancer in rats. The experts pointed out that although the Italian group speculated that the carcinogenicity was caused by a methyl group in aspartame metabolizing into formaldehyde, the body metabolizes methyl groups from other sources without issue; and moreover, reevaluation of epidemiological studies have led to questions over whether formaldehyde can be considered a carcinogen at all.

The new review was sponsored by aspartame supplier Ajinomoto. However the organizers of the expert panel took precautions to ensure that the panelists remained unaware of the name of the sponsor throughout the review process and up until submission and peer review of the manuscript. Likewise, the sponsor was not made aware of the panelists' identities.

Aspartame is a sweetener commonly used in food products for the diet or low calorie market, including soft drinks and chewing gums. It was approved for use in foods in the US and EU member states since the early 1980s. However suspicions have been raised about whether it is entirely safe, and two studies by the Italian Ramazzini group reignited debate after concluding that there was a link between the ingredient and cancer in rats. Although the European Food Safety Authority (EFSA) and the US Food and Drug Administration (FDA) assessed the first study by the Ramazzini group and found no grounds to reevaluate safety of the ingredient or change intake advice.

Sources

1. "Aspartame: A safety evaluation based on current use levels, regulations, and toxicological and epidemiological studies." Critical Reviews in Toxicology. 2007; 37( 8) 629-727.