Validity of Reflection Spectroscopy as a Biomarker of Vegetable and Fruit Intake in a Yu’pik Alaska Native Population (P18-124-19)

Abstract

ObjectivesReflection spectroscopy serves as a biomarker of vegetable and fruit intake by measuring skin carotenoids, however it’s validity in populations who consume high levels of salmon (another source of carotenoids) is unknown. Our objective was to validate reflection spectroscopy as a biomarker for vegetable and fruit intake among Yup’ik Alaska Native people in a remote community who consume a subsistence diet rich in salmon. MethodsWe assessed the convergent validity of a portable reflection spectroscopy device (The Veggie Meter), two 24-hour recalls using NDSR 2018, and the nitrogen stable isotope ratio of hair (a validated biomarker of fish intake) collected from adults (>18 years) in a remote Alaska community. ResultsThe study population (n = 84) was primarily Yup’ik Alaska Native (84%), evenly distributed by sex (45.2% male), and had a mean age of 47.5 years. The mean skin carotenoid score was 222.23 ± 105.81. The median number of fruit servings reported was 0.33 (range = 0 to 4.0), while median servings of vegetables was 1.55 (range = 0 to 11.44). Men had significantly higher skin carotenoid scores than women (202 vs 248; P = .001). Participants who consumed 3 or more servings of vegetables and fruit had a significantly greater Veggie Meter score than participants who consumed less than 3 servings (255 vs 202 respectively; P = .059). The relationship did not change when controlling for fish intake in a general linear model. ConclusionsConsistent with previous findings, vegetable and fruit intake is very low among Yup’ik people. Findings suggest that the Veggie Meter distinguishes between participants who consume high and low levels of vegetables and fruit. Participants consumed lower levels of fish than estimated in previous studies in southwestern Alaska. At this level of fish intake, fish does not appear to confound the relationship between the Veggie Meter and vegetable and fruit intake. Funding SourcesResearch reported here was supported by UAF BLaST, funded by the National Institute Of General Medical Sciences of the National Institutes of Health.