Virgin Olive Oil Study (VOLOS): vasoprotective potential of extra virgin olive oil in mildly dyslipidemic patients

Background: In vitro, olive phenols exert potent antioxidant and enzyme-modulating activities. Aim: We comparatively evaluated, in patients with mild dyslipidaemia, the vasoprotective potential of extra virgin olive oil. Methods: Twenty-two patients from Italy were administered 40 mL/day of either of the 2 extra virgin olive oil samples, i.e. phenol rich or refined (phenol poor) (EVOO or ROO, respectively, with nearly identical fatty acid composition), in a crossover design. Each treatment was carried out for seven weeks, with four weeks of washout in between. Plasma antioxidant capacity, serum thromboxane B2 (TXB2) formation, and urinary isoprostane excretion were evaluated as surrogate markers of cardioprotective potential and vascular function. Results: No effects on plasma lipid/lipoprotein profile were observed. Conversely, EVOO consumption was associated with favourable effects on circulating markers: decreased serum TXB2 production and increased plasma antioxidant capacity were observed when EVOO was administered in both treatment arms. Neither treatment had any significant effect on isoprostane excretion. Conclusions: EVOO consumption by mildly dyslipidaemic patients is associated with favourable changes in circulating markers of cardiovascular condition. Based on current knowledge, these effects may be associated with cardioprotection.