Using Skin Carotenoids to Assess Potential Dietary Changes After One Academic Year in the Shaping Healthy Choices Program

Abstract

Reported dietary intake is often used in community interventions to assess intake of fruits and vegetables (F/V); however, dietary assessment methods are inaccurate, and time and labor intensive. Skin carotenoids are a potential biomarker to assess F/V intake given that carotenoids are predominately found in F/V and their concentration in the skin can reflect dietary intakes of F/V. The Resonance Raman Spectroscopy (RRS) method is a quick and validated method to assess skin carotenoids. The objective of this study was to determine whether skin carotenoids measured by RRS can be used to confirm changes in dietary intake of F/V in 4th‐grade students participating in the Shaping Healthy Choices Program (SHCP). The SHCP is a multi‐component nutrition intervention and one of its aims is to increase F/V intake. Dietary intake was assessed using the Block Food Frequency Questionnaire in a subset of students (n=30) and skin carotenoids were measured using RRS (n=82) before and after the SHCP intervention. Pre‐post changes in F/V intake measured by each method were tested using Student's t‐tests. After 9 months, reported intake of carotenoids decreased by 19% (1469mcg, P=0.05) and skin carotenoids decreased by 9% (2882 RRS intensity units, P<0.001). Change in reported intake correlated with change in skin carotenoids (r=0.43, P=0.02). While the reported decrease in F/V intake in this population was unanticipated given that the intervention aimed to increase intake, the RRS measurements confirmed this change. In conclusion, optically measured skin carotenoids can be used to help evaluate changes after 9 months of F/V intake in 4th‐grade students.Support or Funding InformationFunding was provided by UCANR competitive grant #11‐1018, USDA 2011‐38420‐20082, and USDA NIFA, Hatch project 221082.