Splenda study: Industry and academia respond

Questions have been raised concerning the safety of the Splenda brand of sweetener, and its key component sucralose, following publication of results of a rat study. Both industry and academia gave their views to FoodNavigator.com.

On one side is McNeil Nutritionals, part of Johnson and Johnson, which markets Splenda. The company was quick to dismiss the study and draw attention to a number of other studies supporting the safety of Splenda. The company questioned the methodology and the conclusions drawn by the researchers. Emphasis was also placed on the involvement of the Sugar Association as partial sponsor of the study.

On the other side is the research team from Duke University in North Carolina, and the Sugar Association, which provided funds for the study.

The legal issue

McNeil and the Sugar Association are involved in ongoing legal activity. The Sugar Association initially took action against McNeil Nutritionals regarding Splenda’s old slogan of “Made like sugar, so it tastes like sugar”. The association claimed that this misled consumers into believing that Splenda is a no-calorie natural sugar product.

However, McNeil continues to refute the allegations, claiming that all materials supplied to customers regarding its man-made sweetener are not misleading or deceptive.

The company claims that it promotes the product as a lower calorie alternative to sugar to tap into concerns over increased obesity rates and other health issues.

McNeil launched a countersuit contending that the Sugar Association and others “knowingly and intentionally made false claims about Splenda No Calorie Sweetener that are baseless and designed to injure its reputation and goodwill,” said McNeil in an official statement.

A trial has been set for January 2009.

In July, U.S. District Judge Dale S. Fisher ruled that the results of the rat study cannot be extrapolated to people and are therefore “irrelevant”, according to a statement by McNeil Nutritionals. The court also noted that the researchers’ opinions about the study could be misleading, said the company.

Speaking to FoodNavigator.com, Professor Mohammed Abou-Donia, lead researcher of the new study, said: The Judge accepted our study and conclusions as valid, but decided that because it was done in animals, it should not be extrapolated to humans. Despite the fact that Splenda was approved for use based on animal, mostly rat, studies.

“Last year, before finishing our study, the Sugar Association requested a report that we rushed to them. The report was not proof-read and contained some typographical errors. On the other hand, the final report and manuscript were correct and we stand by all of their findings.”

The funding issue

The study’s funding has been a source of controversy. The role of the Sugar Association in funding the study has been highlighted by McNeil. Indeed, the company refer to it as the “Sugar Association-funded rat study”.

When quizzed by FoodNavigator.com regarding the role of the sponsor Professor Abou-Donia said: All the ideas and methods were my own and my team's. The Sugar Association did not have any input on the research, the results or the conclusions of the study.

“Since the Sugar Association paid for the study only, the overheads were paid by Duke University. No salaries were paid by the Association for Drs. Abou-Donia, McLendon or Schiffman.”

“Their funding paid for the supplies needed for the research and for the salaries of the two junior authors, Dr. Elmasry and Dr. Abdel-Rahman.”

McNeil questions the methodology

The company moved swiftly to counter the study and its results. A fact sheet about the study dismissed it as unreliable and reach[ing] unsupported conclusions”.

The company claims the study “contravenes basic methodological standards for scientific research. It also ignores established FDA standards for Good Laboratory Practices.”

The fact sheet goes on to state the researchers failed to include a control group (which is denied by the researchers), they failed to provide evidence of any effect of the sweetener on enzymes involved in drug absorption, the studies of P-450 enzymes were “inappropriately conducted,” said McNeil, with “inconclusive assessments”.

A spokesperson for the company also added that a journal called Food and Chemical Toxicology published an entire supplement in 2000 devoted to studies on sucralose safety. All of these articles were authored in part or entirely by employees of McNeil.

Defence of the methodology

In an email correspondence with FoodNavigator.com, Professor Sam Kacew, Editor-in-Chief of the Journal of Toxicology and Environmental Health, Part A, expressed his strong support for the methodology used in the study, refuting claims from McNeil that good laboratory practices (GLP) were ignored.

“I want to emphasize and make it absolutely clear that it states in the manuscript, ‘The protocol for these studies was approved by the Duke University Institutional Animal Care and Use Committee ( IACUC)" which means that GLP must be followed,” said Professor Kacew.

“If this is contravened then all funding from NIH to Duke University is terminated,” he added.

“Secondly, this manuscript was sent to three independent experts for evaluation. All three reviewers recommended publication with revisions. The authors revised the manuscript and the revisions were once again sent to the reviewers. All three reviewers recommended publication of the revised manuscript.

“This constitutes a rigourous scientific evaluation of this manuscript,” said Professor Kacew.

To read our report of the study, click here.