Associations between Skin Carotenoids, Sensory Processing, and Developmental Milestones in Midwestern Toddlers across 12 Months

Abstract Carotenoids, antioxidant plant pigments that accumulate in human tissues (e.g., brain, eyes, skin), may positively impact cardiovascular health, vision, and cognition. Skin carotenoids, reflecting total carotenoid intake, are understudied in child development. This research aimed to examine toddlers’ sensory, cognitive, language, and motor development over 12 months and their associations with skin carotenoids. Toddlers (12-18mo at baseline) participated in a 12mo cohort study: baseline ( n = 51), midpoint (18-24mo, n = 46), final assessment (24-30mo, n = 41; 80% completed all timepoints). Skin carotenoids were measured using reflection spectroscopy (Veggie Meter™). Cognitive, language, and motor skills were measured via Bayley Scale of Infant and Toddler Development IV Screening Test (BSID-IV). Mismatch negativity (MMN) and visual evoked potentials (VEPs) were elicited with auditory oddball and pattern reversal tasks, respectively, using electroencephalography. Repeated measures ANOVAs indicated no time effects for skin carotenoids, MMN, or VEPs. Effects were found for BSID-IV cognition, language, and motor skills (all p’s < 0.01). Regressions revealed that baseline skin carotenoids predicted increased gains in cognition from baseline to final timepoint (β = 0.35, p = 0.057), increased gains in fine motor skills from baseline to final timepoint (β = 0.46, p = 0.01) and baseline to midpoint (β = 0.41, p = 0.01), and increased gains in receptive communication from midpoint to final timepoint (β = 0.44, p = 0.01). Baseline skin carotenoids were not related to changes in VEP or MMN outcomes. These findings suggest that skin carotenoids may be linked to cognitive, language, and motor development in toddlers. Interventional research is needed to determine causal effects of carotenoid intake on infant and toddler development.