Relations between dietary and skin carotenoids across 12 months in a midwestern sample of toddlers

Carotenoids, pigments found in fruits and vegetables, accumulate in human tissues after consumption. While cross-sectional studies have linked skin carotenoids to carotenoid intake, longitudinal data in childhood is limited. This study aimed to (1) describe changes in skin carotenoids and carotenoid intake in toddlers across 12 mo, and (2) examine cross-sectional relations between intake of carotenoids and skin carotenoids at each timepoint. We hypothesized positive correlations between carotenoid intake and skin carotenoids. Toddlers participated in a 12mo cohort study with 3 timepoints: baseline (12-18 mo, n = 51), midpoint (18-24 mo, n = 46), and final assessment (24-30 mo, n = 41). Skin carotenoids were measured using reflection spectroscopy (Veggie Meter^TM). Parents completed 3 dietary recalls per timepoint to assess toddler intake. Repeated-measures ANOVAs indicated no significant changes in skin carotenoids; however, significant time effects were observed for tomato [F(2, 74) = 4.61, P = .01], α-carotene [F(2,76) = 4.76, P = .01], and β-carotene intake [F(2,76) = 6.78, P ≤ .01]. Pairwise comparisons revealed increased tomato intake from baseline to final assessment (P < .01), decreased α-carotene intake from baseline to midpoint (P = .01) and final assessment (P = .02), and decreased β-carotene intake from baseline to midpoint (P < .01). Regressions showed a positive relation between egg intake and skin carotenoids at baseline (β = 0.26, P = .04), with no other significant associations at any timepoint. Over the 12-month period, toddlers exhibited increased tomato intake and decreased α- and β-carotene intake. Additional research on toddler dietary patterns is needed to understand their impact on skin carotenoids and to guide targeted dietary interventions.