Despite that fruits and vegetables are key elements for health promotion, there are limited studies validating their intake in children. We aimed to validate the SAYCARE (South American Youth/Child Cardiovascular and Environmental) Study Food Frequency Questionnaire (FFQ) and the combination of the FFQ frequency of intake with the 24 h-dietary-recall (24 h-DR) (mean of 3 days), for children's fruit and vegetable intake. The reference methods were plasma dosages of β-carotene, retinol, ascorbic acid, and α-tocopherol, which were collected in the school environment. It is a validity study in a subsample of 45 children aged 6-10 years participating in the SAYCARE Study, from São Paulo (Brazil). The FFQ was answered by the parents/guardians over the previous 3 months; the 24 h-DR was answered three times (two weekdays by nutritionists, one weekend day by parents/guardians). The mean fruit and vegetable intake (combined with frequency of intake) was calculated using the multiple source method (MSM). Multiple linear regression showed pooled correlation coefficients of 0.29 to 0.35 for the reported fruit and vegetable intake estimated by the FFQ and the MSM, respectively. The SAYCARE FFQ is an accurate and useful tool for ranking fruit and vegetable intake in children between 6-10 years from the SAYCARE Study.
Keywords: 24-h-Dietary-Recall; Multiple Source Method; biomarkers; children; food frequency questionnaire; fruits and vegetables; validity; vitamins.