Abstract
BackgroundFluoride from dietary and environmental sources may concentrate in calcium-containing regions of the body such as the pineal gland. The pineal gland synthesizes melatonin, a hormone that regulates the sleep-wake cycle. We examined associations between fluoride exposure and sleep outcomes among older adolescents and adults in Canada.MethodsWe used population-based data from Cycle 3 (2012–2013) of the Canadian Health Measures Survey. Participants were aged 16 to 79 years and 32% lived in communities supplied with fluoridated municipal water. Urinary fluoride concentrations were measured in spot samples and adjusted for specific gravity (UFSG; n = 1303) and water fluoride concentrations were measured in tap water samples among those who reported drinking tap water (n = 1016). We used multinomial and ordered logistic regression analyses (using both unweighted and survey-weighted data) to examine associations of fluoride exposure with self-reported sleep outcomes, including sleep duration, frequency of sleep problems, and daytime sleepiness. Covariates included age, sex, ethnicity, body mass index, chronic health conditions, and household income.ResultsMedian (IQR) UFSG concentration was 0.67 (0.63) mg/L. Median (IQR) water fluoride concentration was 0.58 (0.27) mg/L among participants living in communities supplied with fluoridated municipal water and 0.01 (0.06) mg/L among those living in non-fluoridated communities. A 0.5 mg/L higher water fluoride level was associated with 34% higher relative risk of reporting sleeping less than the recommended duration for age [unweighted: RRR = 1.34, 95% CI: 1.03, 1.73; p = .026]; the relative risk was higher, though less precise, using survey-weighted data [RRR = 1.96, 95% CI: 0.99, 3.87; p = .05]. UFSG was not significantly associated with sleep duration. Water fluoride and UFSG concentration were not significantly associated with frequency of sleep problems or daytime sleepiness.ConclusionsFluoride exposure may contribute to sleeping less than the recommended duration among older adolescents and adults in Canada.
Highlights
Inorganic fluoride can naturally occur in the environment or be introduced through industrial processes or fluoride supplementation programs
Our study examined the association between fluoride exposure and sleep outcomes in a large Canadian sample using cross-sectional data from Cycle 3 (2012–2013) of the Canadian Health Measures Survey (CHMS)
Multinomial logistic regression of sleep duration and water fluoride levels adjusted for covariates showed a significant association between higher water fluoride and a lower sleep duration; for every 0.5 mg/L higher water fluoride concentration, there was a 34% increased relative risk of reporting sleeping less than the recommended duration (RRR = 1.34; 95% Confidence Interval (CI): 1.03, 1.73; p = .026; Table 3)
Summary
Inorganic fluoride can naturally occur in the environment or be introduced through industrial processes or fluoride supplementation programs. A primary method of fluoride supplementation is community water fluoridation, which refers to the practice of adding fluoridation chemicals to drinking water for the purpose of controlling dental caries. Fluoride in drinking water has consistently been shown to be associated with reduced dental caries in children [1, 4], reducing tooth decay by approximately 30 to 40% [5]. The maximum acceptable concentration (MAC) of fluoride in drinking water in Canada is 1.5 mg/L, with an optimal water fluoride target of 0.7 mg/L to maximize dental benefits while minimizing fluorosis [8]. Fluoride from dietary and environmental sources may concentrate in calcium-containing regions of the body such as the pineal gland. We examined associations between fluoride exposure and sleep outcomes among older adolescents and adults in Canada
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
