Dietary Fiber Is Inversely Associated with Central Arterial Stiffness Progression, While Alcohol and Iron Intake Are Positively Associated with CAVI: A 5-Year Longitudinal Study

Background: Arterial stiffness (AS) is a key marker of vascular aging and an independent predictor of cardiovascular risk. Although diet has been proposed as an important modifiable factor influencing vascular health, the independent associations between specific macronutrients and minerals and the progression of arterial stiffness remain insufficiently characterized. Objective: The aim of this longitudinal study was to evaluate the independent associations of baseline dietary macronutrient and mineral intake with the 5-year progression of arterial stiffness (assessed via carotid–femoral pulse wave velocity (cfPWV) and cardio-ankle vascular index (CAVI) in adults without prior cardiovascular disease. Methods: This longitudinal study included 466 participants from the EVA study who were evaluated at baseline and after a five-year follow-up (mean age 55.96 ± 14.15 years; 51.1% women). Arterial stiffness was assessed using cfPWV and CAVI. Dietary intake of macronutrients and minerals was estimated using the EVIDENT smartphone application. Multivariable linear regression models were used to examine the association between nutrient intake and arterial stiffness progression. Model 1 was adjusted for age and sex, and Model 2 was additionally adjusted for lifestyle variables and cardiovascular risk factors. Dietary intake was exclusively documented at baseline using a 3-day dietary record, while arterial stiffness parameters (cfPWV and CAVI) were assessed both at baseline and at the five-year follow-up. Results: Higher dietary fiber intake was independently associated with a lower increment in cfPWV after full adjustment (β = −0.025; 95% CI (confidence interval): −0.046 to −0.005). Alcohol intake showed a positive association with CAVI increment in the fully adjusted model (β = 0.020; 95% CI: 0.006 to 0.034). Iron intake was also independently associated with increased CAVI (β = 0.022; 95% CI: 0.004 to 0.041). Carbohydrate intake showed a small positive association with CAVI, whereas no consistent independent associations were observed for other macronutrients or minerals. Conclusions: In this adult population without previous cardiovascular disease, higher dietary fiber intake was associated with lower progression of central arterial stiffness, whereas alcohol and iron intake showed positive associations with peripheral arterial stiffness. Overall, most nutrients were not independently related to arterial stiffness after comprehensive adjustment. These findings suggest that selected dietary components may contribute modestly to vascular aging.