Self-Reported Dietary Carotenoid Intake and Skin Carotenoid Score Status in a Geographically Diverse U.S. Sample

Background: The reflection spectroscopy (RS)-based skin carotenoid score (SCS) has been validated to assess carotenoid intake. However, associations between the SCS and individual dietary carotenoid species have been inconsistently reported in the previous literature. This study examined the utility of using a carotenoid screener along with RS to assess individual dietary carotenoid species intake among U.S. adults. Methods: Adults (N = 280) from eight U.S. sites completed a 44-item carotenoid intake screener to estimate total and individual dietary carotenoid intake (α-carotene, β-carotene, β-cryptoxanthin, lutein + zeaxanthin, and lycopene) over the past 7 days. Each participant's SCS was measured using two Veggie Meter^® devices. Spearman's Rank correlation tests and linear mixed models with a random intercept for site were conducted. Results: Mean (± Standard Deviations) carotenoid intake ranged from 21,226.8 ± 9914.1 to 28,863.5 ± 22,462.2 µg/day, and mean SCS ranged from 229.2 ± 72.3 to 325.6 ± 94.1 across the eight sites. Participants' SCS was significantly associated with self-reported total carotenoids (mg)/week (r_s = 0.2 and B = 0.11; p < 0.01) and with all individual carotenoids (r_s ranged from 0.15 to 0.23, p < 0.01; B ranged from 0.11 to 21.1, p < 0.01), except lycopene. Conclusions: Our findings suggest that combining the carotenoid intake screener with RS may offer a practical approach for assessing individual carotenoid species intake in adults.