Abstract
Objectives
Carotenoids are plant pigments that accumulate across several tissues including the macula and skin. However, the relationship between carotenoid deposition in retina and skin is unknown in children. Understanding these interrelationships is important, given that evidence indicates that carotenoid status is a marker of cognitive health in childhood. Importantly, the selectivity of cognitive function to carotenoids in different tissues remains understudied. The present work investigated associations between retinal and skin carotenoids and their implications for children's cognitive function and achievement.
Methods
Children 7–12 years old (N = 50) participated in the study. Retinal carotenoid status, i.e., macular pigment optical density (MPOD), was assessed using heterochromatic flicker photometry. Skin carotenoids were assessed using reflection spectroscopy at the fingertip using the Veggiemeter. Academic achievement was assessed using the Woodcock Johnson IV test and a modified Eriksen flanker task to assess children's ability for selective attention or interference control.
Results
There was a significant positive correlation between skin and retinal carotenoid levels (rs = 0.29, P = 0.02). Skin carotenoids were positively related to reading (rs = 0.42, P = 0.001) and math scores (rs = 0.34, P = 0.009). However, skin carotenoids were not significantly related to flanker interference scores (p's > 0.05). On the other hand, MPOD was positively related to reading (rs = 0.25, P = 0.04) but not math (rs = 0.12, P = 0.20). Further, MPOD was inversely related to flanker interference scores for reaction time (rs = −0.29, P = 0.02) and accuracy (rs = −0.28, P = 0.03), indicating that children with higher retinal carotenoids exhibited superior ability to maintain cognitive control performance when faced with greater task demands.
Conclusions
These findings demonstrate that carotenoid levels in skin and retina are correlated in children. These findings further suggest that carotenoid status in children is associated with cognition, perhaps selectively across site of accumulation and cognitive domains.
Funding Sources
This work was supported by funds provided by the Egg Nutrition Center.