The molecule sucrose – table sugar – is found in a variety of natural and processed food products. While apples, milk and other healthy foods contain vitamins, minerals and fiber besides sucrose, the molecule is often refined and added to sodas, baked goods and candies with little nutritional value other than calories from glucose.
The range of health risks associated with sugar has been debated for decades. This uncertainty, however, may largely be the result of coordinated efforts by the industry to dismiss and withhold evidence that sugar consumption is associated with cancer and other diseases, according to a paper published Tuesday in the journal PLOS Biology.
In the report, researchers from the University of California, San Francisco, present evidence – based on a review of internal sugar industry documents – that the International Sugar Research Foundation (ISRF) launched and subsequently ended prematurely a study that examined the effects of sucrose on cardiovascular health.
Known as Project 259, the study aimed “to measure the nutritional effects of the (bacterial) organisms in the intestinal tract” when rats consumed sucrose, as opposed to starch.
The ISRF-funded research, which was conducted by W.R.F. Pover of the University of Birmingham, suggested gut bacteria helped to offset sugar’s negative cardiovascular effects. Pover also noted findings that might associate sugar consumption with increased risk of bladder cancer.
“This incidental finding of Project 259 demonstrated to ISRF that sucrose vs. starch consumption caused different metabolic effects,” the UCSF team argues, “and suggested that sucrose, by stimulating urinary beta-glucuronidase, may have a role in the pathogenesis of bladder cancer.”
The trade group characterized the finding in a September 1969 internal document as “one of the first demonstrations of a biological difference between sucrose and starch-fed rats.” Pover’s findings were never published, however, as the ISRF terminated the study soon after learning of the results shortly before the research was complete.
In the 1960s, researchers debated whether sugar could elevate triglycerides relative to starch, and the UCSF team argues Pover’s research would have backed up the case that it does.
“The kind of manipulation of research is similar to what the tobacco industry does,” said co-author Stanton Glantz. “This kind of behavior calls into question sugar industry-funded studies as a reliable source of information for public policy making.”
“Our study contributes to a wider body of literature documenting industry manipulation of science,” the team writes. “Based on ISRF’s interpretation of preliminary results, extending Project 259’s funding would have been unfavorable to the sugar industry’s commercial interests.”
Previously, the researchers found the trade group had secretly funded a 1967 article that downplayed evidence linking sugar consumption to heart disease. While that article did note rats fed sugar had higher levels of cholesterol than those fed starch, it dismissed the study as irrelevant to human disease.
All told, the sugar industry as a whole has spent the last 50 years manipulating science to downplay sugar’s role in cardiovascular disease, the researchers say. In 2016, a different trade group criticized a mouse study linking sugar to increased tumor growth and metastasis as not credible.