Skin carotenoid status measured by resonance Raman spectroscopy as a biomarker of fruit and vegetable intake in preschool children

Background/Objective: Dietary assessment in children is difficult, suggesting a need to develop more objective biomarkers of intake. Resonance Raman spectroscopy (RRS) is a noninvasive, validated method of measuring carotenoid status in skin as a biomarker of fruit/vegetable intake. The purpose of this study was to examine the feasibility of using RRS in preschool children, including describing the inter-individual variability in skin carotenoid status and to identify factors associated with the biomarker in this population. Subjects/Methods: We conducted a cross-sectional study of 381 economically-disadvantaged preschoolers in urban centers in Connecticut (U.S.). 85.5% were black non-Hispanic or Hispanic/Latino, and 14.1% were obese and 16.9% were overweight by age- and sex-specific BMI percentiles. Children had their skin carotenoid status assessed by RRS in the palm of the hand. Fruit/vegetable consumption was assessed by a brief parent/guardian-completed food frequency screener and a liking survey. Results: We observed inter-individual variation in RRS values that was nearly normally distributed. In multiple regression analysis, higher carotenoid status, measured by RRS, was positively associated with fruit/vegetable consumption (p=0.02) and fruit/vegetable preference (p<0.01). Lower carotenoid status was observed among younger children, those participating in the U.S. Supplemental Nutrition Assistance Program (SNAP), and those with greater adiposity (p<0.05 for all). Conclusions: We observed wide variability in skin carotenoid status in a population of young children, as assessed by RRS. Parent-reported fruit/vegetable intake and several demographic factors were significantly associated with RRS-measured skin carotenoid status. We recommend further development of this biomarker in children, including evaluating response to controlled interventions.