Plain language summary
The Mediterranean diet is considered one of the most studied diets in scientific literature and this review specifically looks at two fluid aspects of the MedDiet; olive oil and red wine. Olive oil is rich in phenolic compounds and red wine in polyphenols and the study looks at their therapeutic effect on cardiovascular disease prevention, particularly on lipids, blood pressure, plaque and glucose metabolism. Known mechanisms of the MedDiet include reduction of inflammatory and oxidative stress markers, and an improvement in lipid profile and insulin sensitivity. Polyphenols are important antioxidants abundant in plant foods including olives and red grapes used in wine (known to be x10 richer in polyphenols than white wine). The review reports that low to moderate consumption of red wine 30-50g daily lowers risk factors for CVD, improve HDL lipid profile, exerts a beneficial effect on blood pressure (BP), promotes vasodilation thus helping to reduce plaques and finally limited data shows it may beneficially affect insulin resistance. Polyphenols in olives were reported to reduce blood pressure, reduce LDL lipids and increase HDL lipids, support weight loss and help prevent obesity, metabolic syndrome and type II diabetes, reduce inflammation and oxidative stress, and possibility benefit gut microbiota. The review concludes that both fluids exert cardio-protection when consumed in moderation as part of a MedDiet.
A growing interest has emerged in the beneficial effects of plant-based diets for the prevention of cardiovascular disease, diabetes and obesity. The Mediterranean diet, one of the most widely evaluated dietary patterns in scientific literature, includes in its nutrients two fluid foods: olive oil, as the main source of fats, and a low-to-moderate consumption of wine, mainly red, particularly during meals. Current mechanisms underlying the beneficial effects of the Mediterranean diet include a reduction in inflammatory and oxidative stress markers, improvement in lipid profile, insulin sensitivity and endothelial function, as well as antithrombotic properties. Most of these effects are attributable to bioactive ingredients including polyphenols, mono- and poly-unsaturated fatty acids. Polyphenols are a heterogeneous group of phytochemicals containing phenol rings. The principal classes of red wine polyphenols include flavonols (quercetin and myricetin), flavanols (catechin and epicatechin), anthocyanin and stilbenes (resveratrol). Olive oil has at least 30 phenolic compounds. Among them, the main are simple phenols (tyrosol and hydroxytyrosol), secoroids and lignans. The present narrative review focuses on phenols, part of red wine and virgin olive oil, discussing the evidence of their effects on lipids, blood pressure, atheromatous plaque and glucose metabolism.