Abstract

Background: Skin carotenoids measured by reflection spectroscopy (RS) score as a biomarker of fruit and vegetable (F/V) intake has not been used extensively in USA minority populations, and there are concerns about the impact of skin tone on the validity of skin carotenoid scores as a biomarker of F/V intake.
Methods: The aim of this study was to examine the relationship between skin carotenoids measured by RS score, plasma carotenoids, dietary carotenoids, and F/V intake in African American/Black college students and explore the effect of skin tone on RS score readings. One hundred African American/Black students at a Historically Black Colleges and Universities institution participated in this study. RS score was assessed by Veggie Meter, plasma carotenoids measured by high performance liquid chromatography, and dietary carotenoids and F/V intake were estimated by a weekly food frequency questionnaire (FFQ). Skin tone was matched visually and read using a skin swatch on a scale of 1-15, 1 being the lightest and 15 being the darkest. Correlations between RS scores with total plasma carotenoid concentrations, dietary carotenoids, and F/V intake were examined. Multiple linear regression analysis was conducted to assess the relationship of skin tone at the fingertip and inner arm, BMI, and %body fat on the correlation between RS and total plasma carotenoid levels.
Results: Skin carotenoid levels indicated by RS scores were correlated with total plasma carotenoid concentrations (R= 0.595, p<0.01) when controlled for skin tone. RS scores were correlated with total carotenoid intake measured by FFQ (R= 0.249, p<0.05) and total F/V intake per day (R= 0.327, p<0.01) when controlled for skin tone. There was a correlation between total plasma carotenoid levels and total F/V intake (R= 0.206, p<0.05).
Conclusion: Skin carotenoid status measured by RS can be used to approximate blood carotenoid concentrations and F/V intake in African American/Black college student.