Fluoride Action Network

Abstract

Despite increasing concerns about neurotoxicity of fluoride in children, sources of fluoride exposure apart from municipal water fluoridation are poorly understood. We aimed to describe the associations of demographics, drinking water characteristics, diet, and oral health behaviors with plasma fluoride concentrations in U.S. children. We used data from 3928 6–19-year-olds from the 2013–2016 National Health and Nutrition Examination Survey. We used a 24-h dietary recall to estimate recent consumption of fluoridated tap water and select foods. We estimated the associations of fluoridated tap water, time of last dental visit, use of toothpaste, and frequency of daily tooth brushing with plasma fluoride concentrations. The participants who consumed fluoridated (?0.7 mg/L) tap water (n = 560, 16%) versus those who did not had 36% (95% CI: 22, 51) higher plasma fluoride. Children who drank black or green tea (n = 503, 13%) had 42% higher plasma fluoride concentrations (95% CI: 27, 58) than non-tea drinkers. The intake of other foods and oral health behaviors were not associated with plasma fluoride concentrations. The consumption of fluoridated tap water and tea substantially increases plasma fluoride concentrations in children. Quantifying the contribution of diet and other sources of fluoride is critical to establishing safe target levels for municipal water fluoridation.


*Original full-text article online at https://www.mdpi.com/1660-4601/17/24/9205/htm


 

Funding

This research was funded by NATIONAL INSTITUTES OF HEALTH, grant numbers K23ES024803 and R01ES030101 and the Maine Economic Improvement Fund.

Conflicts of Interest

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Appendix A

Table A1. Percent change in plasma fluoride by demographic characteristics and modifiable sources of fluoride consumption among 6–19-year-old National Health and Nutrition Examination Survey participants from 2013–2016.
Table A2. Characteristics of 6–19 year old respondents, by recent green/black tea consumption, National Health and Nutrition Examination Survey, 2013–2016.

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*Original full-text article online at https://www.mdpi.com/1660-4601/17/24/9205/htm