Dietary Fluoride Intake Over the Course of Pregnancy in Mexican Women

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.