Abstract
Fluoride has no tangible health benefits other than preventing dental caries and there is a small difference between its minimum effective dose and its minimum toxic dose. Leading global organizations currently recommend fluoride supplementation because they recommend high-carbohydrate diets which can cause dental caries. Low-carbohydrate diets prevent dental caries making such fluoride recommendations largely unnecessary. A dental organization was among the first to initiate the public health recommendations which started fluoride-supplemented high-carbohydrate nutritional guidelines. This start required expert panels at this dental organization to reverse on three key scientific points between 1942 and 1949: (1) that topical fluoride had potential harms, (2) that dental caries was a marker for micronutrient deficiencies, and (3) that low-carbohydrate diets are to be recommended for dental caries prevention. Internal documents show that private interests motivated the events which led these expert panels to engage in pivotal scientific reversals. These private interests biased scientific processes and these reversals occurred largely in an absence of supporting evidence. It is concluded that private interests played a significant role in the start of public health endorsements of fluoride-supplemented high-carbohydrate nutritional guidelines.

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1. Introduction
   Dental caries is the quintessential disease of civilization, a disease which became prevalent with the start of cereal agriculture and rampant with the start of industrial sugar production [1]. A body of evidence supports the hypothesis that a diet leading to dental caries also leads to chronic non-communicable diseases [2].
   Most authoritative organizations aimed to protect public health ignore this evidence and take the view that dental caries is the only adverse side-effect of their high-carbohydrate nutritional guidelines, a side-effect which can be addressed with universal fluoride recommendations. The intrinsic starches-and--sugar diet which can cause dental caries is described as healthy by the United States Department of Agriculture (USDA) [3]. The carnivorous diet which prevents and stops dental caries is described as a probable carcinogen by the World Health Organization (WHO) [4]. This latter point is raised not to suggest that the carnivorous diet is the only solution for dental caries [5], but as an example to indicate that leading organizations dismiss diets which prevent dental caries and instead rely on fluoride and food fortification to, respectively, address the dental harms and micronutrient deficiencies induced by high-carbohydrate diets.
   The USDA and the WHO not only ignore the evidence that high-carbohydrate diets may lead to diseases other than dental caries, but also fail to prioritize high-quality evidence over low-quality evidence when writing their nutritional guidelines [6,7,8]. The latter observation was made by an expert who coined the term evidence-based medicine and who was a key developer of one of the most widely used evidence-based grading systems [6,7]. The USDA furthermore decided to largely ignore the 2017 recommendations of the National Academies for greater scientific rigor and thus failed to increase the trustworthiness of their scientific processes [9]. Unsurprisingly, editorials in The BMJ have described nutritional guidelines as bold policies based on fragile science [10,11].
   The economic theory of public choice may explain why expert panels with a commitment to public health ignore the principles of evidence-based medicine; organizations may have biased scientific processes within their organization because of the influence of private interests, not necessarily public ones. The aim of this report is to explore the private interests which were present when a dental organization took the first significant steps towards endorsing the current fluoride-supplemented high-carbohydrate nutritional guidelines.