Examining Validity and Sensitivity of Pressure-Mediated Reflection Spectroscopy

The central goal of this proposal is to examine validity and sensitivity of RS-assessed skin carotenoid status as a marker of F\&V intake in a racially and ethnically diverse sample of individuals. First, investigators will examine the association (RS Device Validity) between RS-assessed skin carotenoids and the primary outcomes of objectively-measured plasma carotenoids and self-reported F\&V consumption across four diverse groups: African-American/Black, Asian, White, and Hispanic/Latino (n=213). Then the investigators will conduct a randomized controlled trial to define the relative skin carotenoid responses (RS Device Sensitivity) across racial-ethnic groups, in comparison with plasma carotenoid responses. The investigators will conduct a 6-week randomized controlled trial of a carotenoid-containing juice intervention \[placebo control, low and high dose juice (N=156). Finally, the genetic basis for racial/ethnic group differences in skin carotenoid responses to diet will be investigated through hypothesis-driven genomic analysis of participants from Aims 1 and 2.