Dietary Intake Is Associated with Biomarkers of Lead, Arsenic, and Cadmium in a Cohort of Mexican Adolescents.

Background: Lifestyle changes during adolescence can impact dietary habits and, subsequently, exposure to heavy metals.

Objectives: We aimed to evaluate the associations between food group intakes and metal exposures in a cohort of adolescents.

Methods: This study included 416 adolescents from Mexico City aged 10-18. Sociodemographic information at birth and repeated measurements of diet, anthropometry, and metal exposures were collected over 2 visits 3.5 ± 0.40 y apart (n = 514). Food groups (n = 31) were created based on the characteristics of 119 food frequency questionnaire items and metal dietary sources. Linear mixed-effect models were used to evaluate the associations between food group intake and exposure to blood lead, urinary arsenic, and urinary cadmium for the overall population (main models) and stratified by sex. Models were adjusted for age, sex (main models), maternal age, socioeconomic status, and specific gravity (only for urinary metals).

Results: Fruit intake in girls {2.63% [95% confidence interval (CI): 0.22%, 5.10%]}, and candy in boys [2.13% (95% CI: 0.40%, 3.88%)] and in the whole population [1.38% (95% CI: 0.16%, 2.61%)] were associated with higher blood lead levels. Additionally, leafy greens intake was associated with higher blood lead [10.75% (95% CI: -0.01%, 22.66%)]. Chicken intake in girls was associated with 5.95% (95% CI: 0.38%, 11.84%) higher urinary cadmium. Similarly, the intake of homemade sugar-sweetened beverages in girls [4.42% (35% CI: 0.13%, 8.89%)], and in the whole population [4.14% (95% CI: 1.42%, 6.94%)], was associated with higher urinary cadmium. Moreover, the intake of fish and seafood groups was positively associated with blood lead, urinary arsenic, and urinary cadmium.

Conclusions: We observed associations between food group intake and metal exposures in a group of Mexican adolescents using repeated measures of both outcomes and exposures. We also found that some of these associations varied by sex.