Controversial Sugar Industry Cancer Study Uncovered

Highlights of History

Article claims sugar industry-funded study linked sugar to high blood cholesterol and cancer in rats

Sugar association: study ended without publication partly due to “significant delay”


An old study now sheds new light on the sugar industry’s controversial past, and its secrets are revealed in a new article.

The 1960s study, which suggests a link between a high-sugar diet and high blood cholesterol and cancer in rats, was sponsored by the sugar industry, according to the perspective article published Tuesday. in the journal PLOS Biology.

Yet the study itself has never been published and has been forgotten until now.

“All we know is the plug has been pulled out and nothing has been released,” said Stanton Glantz, professor of medicine at the University of California at San Francisco and co-author of the new article. .

“If the investigator didn’t bother to try, or if he tried and failed, we don’t know. Or if there was some sort of clause in his deal with the sugar folks that prevented him from posting, we don’t know, ”he said.

This enigmatic study seems to provide evidence for the detrimental health effects of excessive sugar consumption. It also suggests that a group then called the Sugar Research Foundation may have manipulated scientific research in its favor, according to the newer. paper.

The authors of the new article previously conducted a separate historical analysis of documents and studies related to the sugar industry.

This analysis, published last year in JAMA Internal Medicine, suggests that the Sugar Research Foundation sponsored a research program that successfully cast doubt on the health risks of a high-sugar diet and instead promoted them. fats “as a dietary culprit” in health problems such as heart disease.

“The kind of scientific manipulation that the tobacco industry has engaged in is exactly the same kind of behavior we’ve documented in these sugar industry articles,” said Glantz, who also studied the industry. tobacco.

The foundation, now called the Sugar Association, spoke out against this analysis last year and challenged PLOS Biology’s new paper, telling CNN that it was “not actually a study, but a study. ‘a perspective: a collection of speculations and hypotheses about events that happened almost five decades ago, led by a group of researchers and funded by individuals and organizations known to criticize the sugar industry.

The association also noted that the study described in the new document ended without publication in part due to “significant delay” and “therefore a budget overrun”.

“We don’t know what would have happened if this study had come out differently and showed no effects of sugar,” Glantz said. “I would bet it would have been published and they would make a lot of noise about it.”

Cristin Kearns, assistant professor at UCSF School of Dentistry and lead author of the article, said she learned about the long-lost study by collecting and analyzing letters between executives at the Sugar Research Foundation and various scientists from 1959 to 1971.

Then she noticed that the study was mentioned in a separate book published by the Sugar Research Foundation, which she found in a public library.

The book “listed all of their research projects between 1943 and 1972, and that project was listed in their report,” Kearns said. “This particular project had no posts, which made me want to know more about the project. ”

The study was called Project 259, and the Sugar Research Foundation initially authorized 15 months of funding for it from June 1968 to September 1969, according to the journal.

As Kearns learned more about Project 259, she discovered that the study had resulted in two findings in rats that, had funding been extended, would have been unfavorable to the commercial interests of the sugar industry, according to the document. .

First, the study showed that urine from rats fed a high-sugar diet appeared to have higher levels of an enzyme called beta-glucuronidase than urine from rats fed a high-starch diet. according to the article.

Beta-glucuronidase has been linked to an increased risk of bladder cancer.

“It was of some political relevance at the time, because there was something called the Delaney Clause, which said the FDA was supposed to exclude carcinogens from the food supply even though they were carcinogens. for animals, ”Glantz said.

Congress passed the Delaney Clause in 1958 to ban the approval of any food additive that could induce cancer in humans or animals.

Project 259 also showed a statistically significant decrease in triglycerides, a type of fat in the blood, in rats fed a diet high in sugar and devoid of bacteria in their intestines, compared to conventional rats fed a basic diet. . Colonies of bacteria in your gut are known as the gut microbiome.

“Basically, they found that to get this high blood triglyceride response in rats fed a high sugar diet, you need bacteria in the gut,” Kearns said.

“So without the bacteria, you didn’t get the high triglyceride response, so that proved to them at the time that the gut microbiome had a role in that high triglyceride response to sugar consumption,” he said. she declared. “I thought it was a fascinating study that they were even looking at the role of the gut microbiome as early as the 1960s.”

In recent years, the gut microbiome has become an area of ​​great interest to researchers.

Still, one limitation of the new paper is that it sheds light on an animal study, and how sugar affects rats may not reflect exactly how it might impact humans.

On the flip side, “I think doing animal studies is an important way to help understand the mechanisms of disease,” Kearns said. “While obviously a rat is not exactly the same as a human, it allows you to conduct experiments in a certain way to learn things that can influence future studies. ”

In its written statement to CNN, the Sugar Association noted that the authors of the new document had not contacted it to verify any of their claims.

“We looked at our research archives and found documents indicating that the study in question was terminated for three reasons, none of which involved potential research results: the study was significantly delayed; it was therefore over budget; and the delay was accompanied by an organizational restructuring, the Sugar Research Foundation becoming a new entity, the International Sugar Research Foundation ”, indicates the association’s statement.

“It was planned to continue the study with funding from the British Nutrition Foundation, but, for reasons unknown to us, this did not happen,” the statement said.

In response, Kearns pointed out that other studies that overlap with this organizational restructuring are still underway.

The Sugar Association statement adds that sugar consumed in moderation can be part of a balanced lifestyle and that the association remains committed to supporting research to better understand the role of sugar in consumers’ diets.

Overall, the new article’s findings were “striking” and “ethical” for Dr Sanjay Basu, an assistant professor of medicine at Stanford University who was not involved in the work.

“The historical background to this is that during the time that these studies took place, many dietary recommendations were made which focused on reducing high fat foods in particular, and in many cases low foods. fat have been replaced by foods high in fat. sugary foods are more palatable, ”said Basu, who has studied the health effects of added sugars in his own research.

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  • “The fact that sugar was not considered to be a substance of concern has unfortunately led to many changes in the American diet that correspond to an increase in obesity and type 2 diabetes,” said Basu.

    “The elimination of this type of study is therefore in part of great concern because of the time in which it took place,” he said. “While we are not sure how much sugar is safe to add, it is quite clear and increasingly evident that we are well above what might be considered reasonable in terms of consuming added sugar as a that country. ”

    Rachel J. Bradford