Correlation of skin carotenoid content with 3-day dietary intake in community dwelling older adults

Pressure-mediated reflection spectroscopy (RS) measures skin carotenoid content (SCC). Continued validation of this method is pertinent to validate its use as an objective measure of fruit and vegetable intake. This study aimed to assess relationships between SCC scores and self-reported dietary carotenoid intake from 3-day food records in community dwelling older adults. This was a cross-sectional analysis of baseline data among cognitively normal older adults (n = 95) participating in the Nutrition Interventions for Cognitive Enhancement (NICE) study. Food-derived vitamin A (R = 0.24, p < 0.05) and food plus supplemental vitamin A (R = 0.29, p < 0.01) were correlated with SCC. All food-derived carotenoids (R: 0.20-0.39, p < 0.05) except beta-cryptoxanthin and lycopene were correlated with SCC. Lutein + zeaxanthin from food more strongly correlated with SCC (R = 0.38, p < 0.001) than combined food plus supplemental intake (R = 0.31, p = 0.002). Correlations for total fruit and SCC (R = 0.23, p = 0.02), total vegetable and SCC (R = 0.31, p = 0.002), and combined total fruit and vegetable and SCC (R = 0.35, p < 0.001) were significant; no sub-categories of fruit or vegetables except dark green vegetables (Rho = 0.4, p < 0.001) had significant correlations with SCC. The current study demonstrates RS-derived SCC scores correlate with 3-day self-reported intakes of F/V and certain carotenoids in community dwelling older adults.