Skin Carotenoids Measured by Reflection Spectroscopy Correlate with Dietary Carotenoid Intake in Racially and Ethnically Diverse US Toddlers from Houston, Texas.

BACKGROUND

Methods to objectively assess fruit and vegetable (FV) intake in young children are needed in order to support rigorous assessments of policies and interventions. Non-invasive skin carotenoid concentration measurements may provide a rapid assessment of toddler carotenoid and carotenoid-rich FV intake. background OBJECTIVE: The aim of this study was to evaluate the relationship between pressure-mediated reflection spectroscopy-measured skin carotenoid scores (SCSs) with proxy-reported carotenoid and FV intake in racially and ethnically diverse, US toddlers.

DESIGN

This study was a secondary analysis of data obtained from a randomized, controlled 10-week study of the effect of an interactive healthy playgroup intervention versus classroom parent education on the diet and physical activity of toddlers. This study collected skin carotenoid and 1-week dietary intake using a 31-item semi-quantitative food frequency questionnaire analyzed by Nutrient Data System for Research nutrient database. The current study determined dietary predictors of toddler SCSs.

PARTICIPANTS/SETTING: Participants were racially and ethnically diverse toddlers (12-36 months) and adult guardian dyads (N=50) recruited from the community in Houston, TX from Fall 2018-Spring 2019.

MAIN OUTCOME MEASURES

At baseline and 10-12 weeks after baseline, SCSs were measured by pressure-mediated reflection spectroscopy (Veggie Meter (TM)), guardians reported toddler diet using a food frequency questionnaire (FFQ), and carotenoid intake was estimated from the FFQ responses using a nutrient database.

STATISTICAL ANALYSIS

The relationship between toddler SCSs and intake of total and individual carotenoid species, and FV servings was tested using generalized linear mixed models, controlling for BMI-for-age percentiles, group assignment, and age.

RESULTS

SCSs were positively and significantly predicted by estimated intakes of total carotenoids (p=0.002), beta-carotene (p=<0.001), and lutein & zeaxanthin (p=0.003). Reported intakes of alpha-carotene, beta-cryptoxanthin, and lycopene were not predictors of SCS. Skin carotenoid scores were predicted by estimated total FV intake (p=0.047) and vegetable intake (p=0.006), but not fruit intake (p=0.580). results CONCLUSION: These results showed that reported dietary carotenoid intake is a significant predictor of SCSs in an ethnically and racially diverse population of toddlers. Toddler skin carotenoid measurement holds promise as a rapid, objective, non-invasive biomarker of dietary carotenoid intake.