A new study on the effects of low daily doses of the artificial sweetener aspartame shows a statistically significant increase in leukemia, lymphoma and breast cancer in rats. Consumer advocates are calling for the FDA to take another look at the safety of aspartame in light of the study, but the FDA seems uninterested.

“Because aspartame is so widely consumed, it is urgent that the FDA evaluate whether aspartame still poses a ‘reasonable certainty of no harm,’ the standard used for gauging the safety of food additives,” said CSPI executive director Michael F. Jacobson. “But consumers, particularly parents, shouldn’t wait for the FDA to act. People shouldn’t panic, but they should stop buying beverages and foods containing aspartame.”

The study, which can be read here, followed a group of 4,000 rats who were given low daily doses of aspartame (comparable to what a dedicated human diet soda drinker might consume, were he/she a rat) beginning during “prenatal” life. The rats were dissected after natural death and the effects of the aspartame calculated. From the study:

The results of this carcinogenicity bioassay not only confirm, but also reinforce the first experimental demonstration of APM’s multipotential carcinogenicity at a dose level close to the acceptable daily intake (ADI) for humans. Furthermore, the study demonstrates that when lifespan exposure to [aspartame] begins during fetal life, its carcinogenic effects are increased

The authors of the study claim that current research on the effects of aspartame are based on studies that did not use a large enough sample of animals and did not allow the animals to live out their natural lifespan.The authors also took issue with a study conducted by the US National Institutes of Health and the American Association of Retired Persons, in which a number of Americans responded to self-administered questionnaires about what they ate and the results compared to their rate of brain cancer.

The FDA responded to the CSPI in an email to Reuters, claiming not to have reviewed the study:

“However, the conclusions from this second European Ramazzini Foundation are not consistent with those from the large number of studies on aspartame that have been evaluated by FDA, including five previously conducted negative chronic carcinogenicity studies,” Herndon said in an e-mail.

“Therefore, at this time, FDA finds no reason to alter its previous conclusion that aspartame is safe as a general purpose sweetener in food.”

The CSPI has downgraded aspartame to “everyone should avoid,” and recommends choosing drinks that contain Splenda instead. CSPI regards Splenda as safe. If you drink a lot of aspartame, or you have kids who do, you might want to read the study and decide for yourself.

FDA Should Reconsider Aspartame Cancer Risk, Say Experts [CSPI]
FDA says unmoved by aspartame/cancer report [Reuters]
Lifespan Exposure to Low Doses of Aspartame Beginning During Prenatal Life Increases Cancer Effects in Rats [Environmental Health Perspectives]

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