The sugar industry convinced the U.S. National Institutes of Health (NIH) that studies that might persuade people to cut back on sugary foods should not be part of a national plan to fight childhood tooth decay, a new study of historical documents argues. The authors say the industry’s activities, which occurred more than 40 years ago, are reminiscent of the tobacco companies’ efforts to minimize the risks of smoking.

University of California, San Francisco (UCSF), health policy postdoc Cristin Kearns came across the 319 letters, meeting minutes, and other documents dating from 1959 to 1971 in the papers of Roger Adams, an organic chemist at the University of Illinois, Urbana-Champaign, who consulted for sugar industry–funded research organizations. Kearns found that sugar companies acknowledged as far back as 1950 that consuming sugar contributed to tooth decay. Yet the industry “adopted a strategy to deflect attention” away from reducing sugar consumption and toward ways of reducing its harms, she and her co-authors write.

For example, sugar and food companies funded research on a vaccine to prevent tooth decay and on adding an enzyme to foods to break up dental plaque. (A 1968 newspaper article headlined “These monkeys may save your teeth” described a monkey lab that was studying the idea of mixing the enzyme with raw sugar.)

In addition, the membership of a sugar industry expert panel was nearly identical to that of a committee at the National Institute of Dental Research (NIDR) working on the 1971 National Caries Program. After gathering the industry group’s input, NIDR included 78% of its recommendations in its first request for research proposals, the UCSF team found in their analysis, published online today in PLOS Medicine. “What didn’t get done is [research on] developing objective tests to categorize foods as to whether they are safe or harmful to teeth,” Kearns says. That lack of information has limited the ability of the U.S. Food and Drug Administration to label certain foods as cavity-promoting, she says.

UCSF co-author Stanton Glantz compares the sugar industry’s tactics with what tobacco companies did in persuading the National Cancer Institute not to fund smoking cessation programs. "Our findings are a wake-up call for government officials charged with protecting the public health, as well as public health advocates, to understand that the sugar industry, like the tobacco industry, seeks to protect profits over public health," Glantz said in a press release. Glantz uncovered tobacco industry documents in the 1990s that led to multibillion-dollar settlements with dozens of state governments.

Lillian Shum, director of extramural research at the National Institute of Dental and Craniofacial Research (the former NIDR), says she can’t comment on the PLOS Medicine study because “that was 40 years ago and there’s nobody still here who was involved.” But the institute’s current research agenda on dental caries includes the role of eating sugary foods, she notes. And the need to limit sugar consumption “is a message that we deliver,” Shum adds.

The Sugar Association, which grew out of one of the industry groups analyzed in the paper, says its staff could not comment directly on the period discussed in the paper. But its statement attacks the paper’s authors for their “use of attention-grabbing headlines and scare tactics that liken consumption of all-natural sugar … to a known carcinogen,” calling it “a ‘textbook’ play from the activist agenda.” The association notes that U.S. dietary guidelines advise the public to lower their risk of cavities by reducing the amount of time that sugars and starches are in contact with teeth before brushing.