Dietary fluoride intake over the course of pregnancy in Mexican women

Abstract

Objective: To estimate dietary fluoride intake (F-) over the course of pregnancy and the overall adjusted difference in dietary F- intake by pregnancy stages and levels of compliance with dietary recommendations. Design: Secondary data analysis from a longitudinal pregnancy cohort study in a population exposed to fluoridated salt. Women were followed during the early, middle and late stages of their pregnancy (n=568). The dietary intake of recommended prenatal nutrients according to Mexican dietary guidelines and F- intake (mg/day) were estimated with a validated Food Frequency Questionnaire. Data were summarized with descriptive statistics. Levels of F- intake were compared to the USA’s IOM Adequate Intake (AI) of 3 mg/day for pregnancy. Adjusted differences in F- intake by pregnancy stages and levels of compliance with recommendations were estimated using random effects models. Setting: Mexico City. Participants: Women participating in the Early Life Exposures in Mexico to ENvironmental Toxicants (ELEMENT) project, from 2001 to 2003. Results: Median dietary F- intake (IQR) throughout pregnancy ranged from 0.64 (0.38) in the early-, to 0.70 (0.42) in the middle-, and 0.72 (0.44) mg/day in the late-stage (0.01 mg F-/kg/day). Corresponding adjusted intakes of F- [95% CI] were 0.72 [0.70-0.74], 0.76 [0.74-0.77], and 0.80 [0.78-0.82] mg/day. Women who were moderately and highly compliant with Mexican dietary recommendations ingested, on average, 0.04 and 0.14 mg F-/day more than non-compliant women (p<0.005). Conclusions: Dietary F- intake was below current AI, was greater with the progression of pregnancy and in women who were moderately and highly compliant with dietary recommendations.