Biomarker-based validity of a food frequency questionnaire estimating intake in Brazilian children and adolescents

This study evaluated the validity of nutrient and food group intakes estimated by an FFQ against biomarkers. A 71-item semiquantitative FFQ was administered to 210 Brazilian children and adolescents aged 9-13 years. Intakes were correlated with biomarkers in plasma and red blood cells. Correlations between nutrients and their biomarkers were presented for animal protein, myristic acid (C14:0), EPA, DHA, beta-carotene, folate, and vitamins B3, B5 and B6. Food groups and biomarkers were correlated as follows: fish products with EPA and DHA; milk and dairy with C14:0, pyridoxal 5'-phosphate and vitamin B12; total vegetables and dark green and orange vegetables with beta-carotene; 5-methyltetrahydrofolate with green vegetables; and flour products with para-aminobenzoylglutamic acid. This FFQ is a valid tool for ranking Brazilian children and adolescents according to their intake of several nutrients and food groups.

Automated summary

The study assessed the validity of nutrient and food group intake estimated by an FFQ against biomarkers in Brazilian children and adolescents aged 9-13 years. Results showed correlations between nutrient intake and biomarkers, indicating the FFQ is a valid tool for ranking individuals based on their intake of various nutrients and food groups.