Note: The Warren study (2009) ends with this observation: “Despite the limitations, the study provides the only recent, outcome-based assessment of the ‘optimal’ fluoride intake, and as such, it appears that while the generally accepted range of 0.05 to 0.07 mg F/kg bw may still be associated with caries prevention, it may not be optimal in preventing fluorosis. Of course, given that most caries prevention is believed to be as a result of topical exposures, it may be of little lesser consequence as to what the ‘optimal’ fluoride intake level is for caries prevention. By the same token, while limiting fluoride intake to less than 0.05 mg F/kg bw may be appropriate to prevent fluorosis, given that most fluorosis were mild even at higher intake levels, recommendations to limit fluoride intake to less than 0.05 mg F/kg bw may not be justified. Thus, given that the present study found considerable overlap among caries/fluorosis groups in terms of mean fluoride intake and extreme variability in individual fluoride intakes for those with no fluorosis or caries history (Figure 2), firmly recommending an “optimal” fluoride intake is problematic, and as stated by Burt and Eklund, perhaps it is time that ‘the term optimal fluoride intake be dropped from common usage.’” Source: Ibid. Warren, et al. (2009) pp. 114-115.