The US sugar industry funded an animal research in the 1960s to look into the effects of sugar consumption on cardiovascular health, but the results were never published.
The old study is now shedding new light on the controversial past of the sugar industry: Its documents were uncovered by researchers at the University of California, San Francisco, and published in the journal PLOS Biology on Tuesday.
The documents show that a trade group called the Sugar Research Foundation, which is now known as the Sugar Association, funded the research project on animals. But, when it was found that sugar might promote not only heart disease but also cancer, the industry ended the study and never published the results.
Despite a number of studies, the sugar industry has always insisted that sugar has no unique role to play in promoting obesity, diabetes or heart disease.
The researchers say this kind of manipulation on the part of the sugar industry continues. In fact, last year, the Sugar Association criticised a mouse study suggesting a link between sugar and increased tumour growth, saying that "no credible link between ingested sugars and cancer has been established".
Stanton Glantz, a professor of medicine at UCSF and an author of the new report, said even though the newly-discovered documents are 50 years old, they are important as they point to a decades-long strategy to hide the potential health effects of sugar consumption.
In a statement, the Sugar Association called the report "a collection of speculations and assumptions about events that happened nearly five decades ago, conducted by a group of researchers and funded by individuals and organisations that are known critics of the sugar industry."
They also added in the statement that sugar "consumed in moderation is part of a balanced lifestyle."
They sid they remained "committed to supporting research to further understand the role sugar plays in consumers' evolving eating habits."
Glantz told Daily Mail Online: "The sugar industry has been playing the same games as Big Tobacco to protect their financial interests.
Glantz, who has also studied the tobacco industry, added: "The kind of science manipulation that the tobacco industry engaged in is exactly the same kind of behaviour that we've documented in these papers from the sugar industry."