As the debate over the health impact of sweetened beverages continues, some research studies are funded by beverage makers themselves. And several clauses in contracts between Coca-Cola and health researchers at public universities in the U.S. and Canada could have allowed the soda giant to “quash” the findings, a new study found.

While researchers did not find any firm examples of Coca-Cola suppressing unfavorable findings, study authors said that “what is important is that the provision exists." The paper was published Tuesday in the Journal of Public Health Policy.

The British and Italian researchers, along with the group U.S. Right to Know, were concerned about conflicts of interest in commercially funded research and any influence companies paying for such work may assert.

They chose Coca-Cola as their study example and filed 129 Freedom of Information Act requests between 2015 and 2018 that generated more than 87,000 documents involving five research agreements with Louisiana State University, and the Universities of South Carolina, Toronto, and Washington.

The documents showed that Coca-Cola — which supports research in nutrition, physical inactivity, and energy balance — did not have day-to-day control but retained rights throughout the process that included receiving updates and comments on findings prior to research publication and the ability to terminate the study at any time without cause.

“These contracts suggest that Coke wanted the power to bury research it funded that might detract from its image or profits,” said Gary Ruskin, co-director of U.S. Right to Know.

Coke would not agree to an interview.

In a statement, the company said it implemented new guidelines in 2016 stating it would no longer provide all of the funding for scientific research and that other entities must provide at least 50 percent of the research costs.

As part of its guidelines the company stated “...that we do not have the right to prevent the publication of research results nor do we provide funding conditioned on the outcome of the research.”

The finding comes at a time when U.S. cities – including Philadelphia – and other countries are introducing taxes on sugary beverages. Some municipalities have said they are doing so to combat health problems such as obesity. Philadelphia has framed its tax as a way to raise money for public programs such as parks and preschool.

Nearly 40 percent of U.S. adults and about 18.5 percent of children are considered obese, the Centers for Disease Control and Prevention reported.

According to the World Health Organization, obesity across the globe has nearly tripled since 1975. In 2016, more than 1.9 billion adults 18 years and older were considered overweight, with 650 million classified as obese. About 340 million children and adolescents ages 5 to 19 and 41 million children under age 5 are considered overweight or obese.

The researchers called on corporations to publish lists of terminated studies. They also suggested that journals require authors whose research is funded by companies with a vested interest in the outcome to upload the agreements as appendices to any peer-reviewed publication to demonstrate that any findings are “free from influence.”

“The lack of robust information on input by industry and on studies terminated before results are published, makes it impossible to know how much of the research entering the public domain reflects industry positions," said lead author Sarah Steele, with the University of Cambridge Department of Politics and International Studies.