Lifestyle Factors and Diet-Disease-Related Knowledge: A Network Psychometric Analysis of Cardiovascular Health Literacy Among Lebanese Adults

Background/Objectives: Diet-disease-related knowledge (DDRK) is theorized to foster healthier lifestyles; however, the structural interconnectedness between nutritional knowledge and personal biomarker awareness is not well understood. This study aimed to identify independent predictors of DDRK and cardiovascular health (CVH) literacy among Lebanese adults using a psychometric framework. Methods: A cross-sectional convenience-sampled online survey was conducted among 406 Lebanese adults. Standard validated questionnaires were used, including the GNKQ-Section 4, GPAQ, and MEDAS. CVH literacy was computed as the total awareness of five main CV biomarkers: total cholesterol, LDL, HDL, triglycerides, and HbA1c. Data were analyzed through multivariable logistic regression and EBICglasso network analyses. Results: Overall, the prevalence of cardiovascular (CV) biomarker unawareness was 65.5% across participants. Fully adjusted regression models showed that a continuous DDRK score was a significant factor independently associated with lower odds of CV biomarker unawareness (aOR = 0.878, 95% CI [0.824–0.936], p < 0.001), followed by a higher MEDAS score (aOR = 0.842, p = 0.003) and aging (aOR = 0.961, p < 0.001). The network model was dense (sparsity = 0.133) and showed DDRK–CVH literacy as the strongest conditional edge (rpartial = 0.202). The conditional associations of BMI (r = 0.000) and physical activity (r = 0.036) with CVH literacy collapsed after conditioning on DDRK and MEDAS. Centrality indicators showed that DDRK had the highest closeness and strength (both = 1.000). Conclusions: DDRK shows strong conditional network associations with Mediterranean diet adherence and CVH literacy. These exploratory findings generate hypotheses for future longitudinal or interventional research.