Sugar Industry Influence on the Scientific Agenda of the National Institute of Dental Research’s 1971 National Caries Program: A Historical Analysis of Internal Documents

Data Sources

Emergence of the National Caries Program, 1966–1967

Table 1 provides a timeline of events during the planning and launch of the NCP.

In June 1966, President Lyndon Johnson initiated a major reappraisal of National Institutes of Health (NIH) research agendas, requesting that directors of NIH institutes submit their programs’ “priorities and objectives in the national attack on disease and disability” [29]. The NIDR Director Seymour Kreshover’s report to President Johnson in November 1966 stated that “an accelerated program of research during the next decade could reasonably provide the means for virtual eradication of dental caries” [31].

The threat of the NIDR’s dental research program to the sugar industry began to crystallize in July 1967, after the president praised Kreshover’s report [31]. While it had long been known that bacteria caused tooth decay [54], Kreshover based his plans on the work of NIDR scientists Robert Fitzgerald and Paul Keyes, who had singled out the bacterial strain Streptococcus mutans as a major culprit in the production of acids that caused dental caries [55,56]. Research suggested that sucrose was more hazardous than other types of sugars because it caused S. mutans to form dextrans, sticky molecules that caused the bacteria to tenaciously adhere to one another in the plaque and on the tooth’s surface [57]. The NIDR’s increased interest in S. mutans brought renewed scrutiny to sucrose consumption and dental caries risk.

In October 1967, the NIDR’s National Dental Advisory Council identified three main areas of emphasis to inform research priorities to eradicate caries: reducing the virulence of bacteria once exposed to sugars, fluoride delivery, and, of most concern to the sugar industry, dietary modification [31]. A particular threat was research conducted by NIDR scientist Robert Stephan, initiated in the 1940s, on the “cariogenic” (decay-causing) potential of foods [58–60]. According to Stephan, as of 1966:

There have been a great many observations, discussions, and controversies published in the literature concerning the role of different foods and particularly sweets in the etiology [of dental caries]. However…there seems to be little controlled experimental proof to show which foods are cariogenic and which noncariogenic in humans. [61]

Stephan had initiated work to develop an animal model that could “evaluate cariogenicity and anticariogenicity of different foods and beverages that people like and commonly consume” [61]. Based on existing research at the time, foods containing sucrose were in danger of being placed at the top of the list of harmful cariogenic products [62].

Industry Deflection of Attention Away from Limiting Sugar Intake

Setting Research Priorities for the National Caries Program, 1968–1969

At a June 1968 press conference, NIDR Director Kreshover announced the creation of the Caries Task Force chaired by NIDR Laboratory of Microbiology chief Henry Scherp to develop the NCP [31]. A subcommittee, the Caries Task Force Steering Committee, was assigned the essential task of identifying research priorities [29]. Task force members were largely drawn from federal agencies and academia (Table 2). Professor Basil Bibby, with a strong background in developing models that could evaluate the cariogenicity of foods, would be assigned a leading role in evaluating research supporting dietary interventions to eliminate tooth decay [29].

In 1968, SRF reorganized as ISRF to carry on SRF’s research mission at the global level [48]. Existing SRF research projects, including Project 269, continued to be supported by ISRF [67]. ISRF was also interested in engaging federal research agencies. On July 1, 1968, Dr. Philip Ross became ISRF president [48]. Ross had ties to the NIH, having served as chief of the NIDR/NIH Research Grants Section from 1963 to 1965, then as assistant head of the NIH Special International Programs Section until 1967 [49]. Moreover, that summer, ISRF moved its headquarters from New York to Bethesda, Maryland, near the NIH [68].

Launch of the National Dental Caries Program, 1970–1971

During his February 1970 budget message, President Nixon announced support for “substantial increases in research on cancer, heart disease, serious childhood illnesses, and dental health—where current findings promise significant advances for the future” [31]. A line item in the budget allocated US$5 million (US$30.6 million in 2014 dollars) for the NCP in fiscal year 1971 [29].

In February 1970, after President Nixon’s public endorsement of the NCP but before the NIDR officially released the NCP research priorities, ISRF mailed its report International Sugar Research Foundation Special Report: Dental Caries [50] to its Scientific Advisory Board. The ISRF report began, “The correlation between sugar and dental decay—a practical concern of the sugar industry for many years—may become a purely academic issue within the foreseeable future,” then described the work ISRF leaders had invested to influence the NCP [50]. ISRF President Ross had collaborated with the NIDR Caries Task Force Chairman Scherp and had submitted a report created by ISRF staff on dental caries research priorities directly to the NIDR Caries Task Force:

Dental caries has been a constant worry to many consumers of sugar and sugar products. To some scientists, dental caries and sugar are considered almost “synonymous.” ISRF, in its concern about this image, has supported research to uncover many of the unknowns, and has kept in close communication with other institutions which concentrate on such research. The National Institute of Dental Research, of the U.S. Public Health Service’s National Institutes of Health, is the most prominent U. S. organization conducting dental caries research on a broad scale. Last year the Institute formed a Dental Caries Task Force to work “toward the goal of virtually eliminating tooth decay in the United States.” Dr. Philip Ross, ISRF President, met with the Dental Caries Task Force and has worked closely with its Chairman, Dr. Henry W. Scherp. Dental Caries Research—1969, prepared several months ago by the staff of ISRF, reviewed current knowledge of the subject and was submitted to the Task Force for its consideration. [50]

The NIDR Caries Task Force held its conference on dietary research priorities one month later (Table 1) [42]. At the NIDR Role of Human Foodstuffs in Caries Workshop Conference, Caries Task Force Steering Committee member Basil Bibby presented a paper, “Methods for Comparing the Cariogenicity of Foodstuffs,” which reviewed the status of research on experimental models to identify food products harmful to teeth [43]. These models were important, according to Bibby, because it was “desirable to have a relatively speedy and economical method of evaluating cariogenicity, especially of snack-type foods, so that parents can be warned against the more destructive products” [43]. Bibby’s presentation summarized 12 different models to identify the cariogenicity of foods, ranging from “acid production from foods incubated in saliva” to the production of caries in rats, monkeys, and pigs [43]. During the discussion of Bibby’s presentation, Caries Task Force members established that “a quick screening method was needed to provide presumptive evidence of the potential cariogenicity of accepted foods and new products that appear almost daily on the shelves of food markets,” although there were differences of opinion on what the best model would be to screen for cariogenicity [44]. No one argued that the NIDR not pursue standardization of a test that would rank foods on their potential for tooth decay [44].

Comparison of ISRF and the NIDR Research Priorities

Soon after Nixon’s February 1970 endorsement of the NCP, Scherp began operational planning for program implementation at the NIDR [29]. Research priorities were first published in an omnibus request for contracts (RFC) [29] titled Opportunities for Participation in the National Caries Program [30] in early 1971. The NIDR received 112 proposals and funded 17 contracts [29] totaling US$3 million (US$18.3 million in 2014 dollars) out of the NCP’s budget of US$6 million (US$36.7 million in 2014 dollars) [31]. While the 1971 NCP RFC was the first of several RFCs [73], it established the NIDR’s research priorities for years [29].

The research priorities in the 1971 NCP RFC largely reflected the research priorities identified at the October 1969 NIDR Caries Task Force Steering Committee meeting (compare columns C and G in Table 3). Despite being published nearly a year after the NIDR Caries Task Force Role of Human Foodstuffs in Caries Workshop Conference (Table 1), the 1971 NIDR RFC omitted developing a standardized model to identify the cariogenicity of foods as a research priority.

Comparison of the research priorities identified by ISRF and submitted to the NIDR in 1969 (Table 3, column E) with those published by the NIDR in its 1971 NCP RFC (column G) shows that ISRF and the NIDR research priorities were largely aligned. Indeed, a side-by-side comparison of overlapping text from the ISRF submission to the NIDR, Dental Caries Research—1969 [46], and the 1971 NCP RFC, Opportunities for Participation in the National Caries Program [30], reveals that 78% of the ISRF submission to the NIDR was directly incorporated into the 1971 NCP RFC. (S1 Table provides the actual text from the ISRF submission and 1971 NCP RFC.) Of the 274 total lines in the 1971 NCP RFC describing research priorities, 110 lines, or 40%, were taken verbatim or closely paraphrased from the ISRF submission. Of these 110 lines, 34% were copied verbatim from the ISRF report, and 66% were paraphrased.

The 1970s Missed Opportunity

The majority of the research priorities promoted by the sugar industry and those selected for the 1971 NCP RFC failed to lead to widespread application [31]. By 1976, clinical studies of dextranase mouth rinses in humans had failed to duplicate the success of using dextranases to inhibit new dental caries in experimental animals [31]. The NIDR found that the pharmaceutical industry had limited interest in research, development, and distribution of antimicrobial agents, because of the high cost of regulatory approval by the Food and Drug Administration (FDA) and doubts about identifying an agent that would be successful on a large scale [31]. By 1977, NCP researchers had found that their plan to substitute sucrose with a mixture of glucose and fructose “would effect little reduction in food cariogenicity” [29]. In addition, by 1978, the NIDR had terminated clinical trials on phosphates added to foods because they were ineffective [31].

The most successful interventions selected for funding following the 1971 NCP RFP were topical fluoride and sealants [31]. While a 1980 prevalence survey found that the burden of dental disease in children had decreased by more than 30% since the last survey in 1971–1973, 64% of children still exhibited dental caries, far short of the NCP’s founding goal of eradicating the disease [31].

It is not clear why the NIDR adopted the position in 1969 that reducing sugar intake as a public health measure was impractical. Proposals centered on ways to limit sucrose consumption were just around the corner. In its multi-year review of foods generally recognized as safe initiated in 1969, the FDA deemed sucrose consumption at 1976 levels as unsafe for teeth [77]. In the coming years, the FDA would consider food labels “to warn against the hazards to the teeth of consuming a particular product” and debate whether warning labels should be placed on foods based on the percentage of sugar content, or on some measure of cariogenic potential [78].

When reflecting on the NCP in 1990, Basil Bibby, a member of the Caries Task Force Steering Committee, noted that the NIDR approved only “one or two small research grants” related to food cariogenicity compared to the “hundreds of generous awards [that] were made for investigations with so-called high scientific content” [79]. He also noted that since the NIDR was the major funding source for dental research in the US, “the failure of the National Institute for Dental Research to support research on foods meant that there was no group of investigators in the United States who had enough financial support to undertake significant research on food cariogenicity” [79].

In 1977, the NIDR finally moved to develop a standardized animal model to identify the tooth-decay-causing potential of foods “with the objective of its being widely accepted in industry, and in regulatory agencies and in academic research, as a basis for distinguishing cariogenic from non-cariogenic snacks” [29]. While research on an animal model was initiated at the NIDR [29], the bulk of the research was conducted outside the NIDR, largely funded by the American Dental Association Health Foundation [80]. Based on the promise of the development of a standardized model to identify harmful foods, in 1978 the US Federal Trade Commission proposed restrictions on advertising cariogenic products to children [81]. The first US Department of Health and Human Services Healthy People objectives, issued in 1980, proposed banning cariogenic products from schools as a means to control dental caries [82]. While lobbying efforts of the food, advertising, and broadcasting industries were a major reason for the failure of the FDA, Federal Trade Commission, and Healthy People proposals, another common factor cited for these policy failures is the lack of a standardized model to identify foods harmful to teeth [78,81,83].

With industry input, consensus was finally achieved on a standard method to screen foods for cariogenicity at a conference sponsored by the Foods, Nutrition and Dental Health Program of the American Dental Association in 1985, but only to support claims that food products were safe for teeth [84]. In 1996, the FDA began allowing health claims (i.e., “does not promote tooth decay”) on food products containing sugar substitutes based on a standard screening method for cariogenicity [85]. The FDA did not, however, require disclosure or labeling of harmful foods. In 1999, a group of clinicians and dental scientists updated the methodology agreed upon in 1985 with the aim of identifying which methods were “suitable as research tools but also for regulatory assessments” [86]. However, the use of these methods to identify foods harmful to teeth remained controversial [87].

With the implementation of the nutrition facts panel on packaged food products in 1993, the FDA required the declaration of total sugars [88], a requirement that remained unchanged as of January 2015. As of January 2015, the FDA was considering a proposed rule to require disclosure of added sugars on the nutrition facts panel [88], and SA was opposing it, citing “the lack of science to justify ‘added sugars’ labeling” [89].

Comparison to the Tobacco Industry

The sugar industry formed SRF in 1943 to fund research that supported the industry position [34], 11 years before the creation of the Tobacco Industry Research Committee (TIRC) in 1954 to play a similar role for the tobacco industry [90]. In 1954, the TIRC hired SRF’s first scientific director, Robert Hockett, to serve as the TIRC’s associate scientific director [91], where he was positioned to help the tobacco industry learn key science manipulation tactics from the sugar industry.

At the same time that the NIDR was planning the NCP, the National Cancer Institute (NCI) was pursuing its Smoking and Health Program [92–94]. Like NCP, which focused on sugar harm reduction strategies, the Smoking and Health Program focused on harm reduction strategies with the primary goal of developing a safe cigarette [93]. The NCI invited tobacco industry representatives to join the NCI’s Tobacco Working Group (TWG), the planning committee for the effort to develop a less hazardous cigarette [93]. The NCI did so on the assumption that tobacco manufacturers were interested in promoting new, safer cigarettes and had product expertise the NCI lacked [94]. The NCI also believed industry participation was advantageous because implementation would fall to tobacco companies and, if approached in a positive way, the companies would agree to collaborate [94]. The willingness of the NIDR leaders to interact with the sugar industry during planning for the NCP may have reflected similar thinking, particularly because responsibility for manufacturing and incorporating additives to reduce the risk of dental caries would fall to food and pharmaceutical industries.

The tobacco industry used its involvement in the TWG to oppose funding of projects, such as smoking cessation programs, that were seen as a threat to industry interests [94]. The tobacco industry also withheld knowledge about the biological effects of cigarette smoke and human smoking behavior, which negatively impacted the NCI’s efforts [94]. Indeed, industry use of the TWG to block effective tobacco control strategies was cited by federal Judge Gladys Kessler in her 2006 ruling that the major cigarette companies and their research and lobbying organizations had formed an illegal enterprise to defraud the public in violation of the Racketeer Influenced and Corrupt Organizations Act [95].

Litigation against tobacco companies has been a major factor in achieving meaningful policy change. Successful litigation could not have been achieved without industry documents research illuminating the strategies and tactics of tobacco companies. This analysis demonstrates that sugar industry documents research has the potential to define industry strategies and tactics, which may potentially prove useful in future litigation.

Limitations

While we were fortunate to discover the Roger Adams papers, we recognize that it provides a narrow window into the activities of just one sugar industry trade association, particularly because other industries had an interest in the outcome of the NCP, including the chocolate and confectionary industries, the pharmaceutical industry, and food companies interested in developing food additives and sugar substitutes. To help compensate for limited access to industry documents, we used other historical materials to cross-validate findings as they emerged throughout the analysis. Another limitation was that we could not interview key actors.

Conclusion

This historical example illustrates how industry protects itself from potentially damaging research, which can inform policy makers today. While it may be valuable in theory for the industry to contribute data about their products to the research community, industry should not have the opportunity to influence public health research priorities [94]. Regulatory science to support sensible and defensible policies to limit added sugar consumption was not pursued in the 1970s because of the alignment of the NIDR’s research priorities with those of the sugar industry. Actions taken by the sugar industry to impact the NIDR’s NCP research priorities, which echo those of the tobacco industry, should be a warning to the public health community. The sugar industry’s current position—that public health recommendations to reduce dental caries risk should focus on sugar harm reduction as opposed to sugar restrictions—is grounded in more than 60 years of protecting industry interests. Industry opposition to current policy proposals—including a WHO guideline on sugars proposed in 2014 and changes to the nutrition facts panel proposed in 2014 by the FDA—should be carefully scrutinized to ensure that industry interests do not supersede public health goals.