Biochemical Validation of a Self-Administered Carotenoid Intake Screener to Assess Carotenoid Intake in Nonobese Adults

Abstract

BackgroundEpidemiological studies have demonstrated an association between carotenoid intake and health. However, an accurate measurement of carotenoid intake is challenging. FFQ is the most commonly used dietary assessment method and is typically composed of 100–200 items. However, the greater participant burden that accompanies a more detailed FFQ provides only a marginal gain in accuracy. Therefore, a brief validated carotenoid intake screener is needed. ObjectivesTo conduct secondary analysis evaluating the validity of a newly developed 44-item carotenoid intake screener from The Juice Study: Sensitivity of Skin Carotenoid Status to Detect Change in Intake (NCT03202043) against corresponding plasma carotenoid concentrations (primary) and skin carotenoids (secondary) in nonobese Midwestern American adults. MethodsHealthy adults (n = 83; 25 men and 58 women) aged 18–65 y (mean age, 32 ± 12 y) with a BMI (in kg/m2) of 18.5–29.9 (mean BMI, 25 ± 3) were recruited between 25 April 2018 and 28 March 2019. Participants completed the carotenoid intake screener weekly during the 8-wk parent study. Plasma carotenoid concentrations were assessed at weeks 0, 4, and 8 using HPLC. Skin carotenoids were assessed weekly using pressure-mediated reflection spectroscopy (RS). Correlation matrices from mixed models were used to determine the correlation between carotenoid intake and plasma and skin carotenoids over time. ResultsThe total carotenoid intake, as determined by the carotenoid intake screener, correlated with both the plasma total carotenoid concentration (r = 0.52; P < 0.0001) and the RS-assessed skin carotenoid concentration (r = 0.43; P < 0.0001). Correlations between reported intake and plasma concentrations of α-carotene (r = 0.40; P = 0.0002), cryptoxanthin (r = 0.28; P = 0.0113), and lycopene (r = 0.33; P = 0.0022) were also observed. ConclusionsThe results of this study demonstrate an acceptable relative validity of the carotenoid intake screener to assess total carotenoid intake in adults classified as those having a healthy body or those with overweight.