Validation of a Food Frequency Questionnaire for Vitamin D and Calcium Intake in Healthy Female College Students

Abstract

Objective: The objective of this study was to examine the reproducibility and validity of a Food Frequency Questionnaire (FFQ) and assess calcium and vitamin D intake in health female college students. Methods: Thirty-five healthy female students were conveniently selected to participate in the study. None of the subjects were taking any supplements. The FFQ was validated against intakes from a three-day diet food record report (FR). Results: Positive correlations were observed of daily vitamin D (r = 0.82, p < 0.001) and calcium intake (r = 0.74, p < 0.001) derived from FFQ compared with the FR. The mean intake of vitamin D and calcium derived from FFQ and FR were (233 ± 90, 654 ± 391) and (231 ± 79, 611 ± 352), respectively. The FFQ overestimated vitamin D and Calcium by 2 IU /day (95% CI: −8, 9, p < 0.676 and 43 mg/d (95% CI: 20, 65, p < 0.01). Conclusions: The FFQ used in this study shows promising validation evidence to be used in the future for assessing vitamin D and calcium intakes in female students.