Nutrition Knowledge, Food Insecurity, and Dietary Biomarkers: Examining Fruit and Vegetable Intake Among College Students

Objectives: Food insecurity among college students, combined with limited nutrition knowledge and barriers to healthy eating, significantly impacts diet quality and fruit and vegetable intake. Efforts to address these issues are further complicated by the challenges of accurately and efficiently collecting dietary data in research settings. This study aimed to explore the relationship between nutrition knowledge and fruit/vegetable intake using skin, plasma, and dietary carotenoid levels as biomarkers. Methods: Undergraduate and graduate students aged 18 years and older (n = 166) from a California public university were recruited. The sample was predominately female (n = 133, 80%), with 30 males (18%) and three individuals (2%) identifying as non-binary. Food security was assessed using the USDA's 10-item Adult Food Security Survey Module and nutrition knowledge through a validated questionnaire. Biological data included blood samples and skin carotenoid measurements (Veggie Meter (R)). Dietary quality (HEI-2015) and carotenoid intake were assessed through Diet ID (TM), a photo-based assessment tool. Results: The mean nutrition knowledge scores were 36.55 +/- 8.83 out of 58 points, and the mean skin carotenoid score was 307.07 +/- 110.22. Higher knowledge scores were associated with increased plasma carotenoids, HEI-score, and Diet ID (TM) total carotenoids. Food security classification did not significantly impact nutrition knowledge but did influence HEI scores and skin carotenoid levels, with very low food security linked to poorer diet quality and lower carotenoid levels. Conclusions: Nutrition knowledge may serve as a significant predictor of fruit and vegetable intake in university students. Despite this correlation, the impact of overall diet quality is potentially hindered by an individual's food security status. Therefore, while knowledge is critical, addressing food insecurity is essential for enhancing diet quality among college students.