A Novel Functional Refined Olive Oil, Enhanced with Orange Peel Extract, Modulates Postprandial LDL-Cholesterol Responses in Individuals at Cardiometabolic Risk: A Pilot Randomized, Controlled, Cross-Over Nutritional Intervention

Abstract

Olive oil, as the main source of polyphenols in the Mediterranean diet pattern, is mentioned to show remarkable postprandial bioactivity, contributing to the reduction of cardiometabolic risk factors. In recent years, the consumption of refined olive oil, instead of other olive oil classes, led to a reduced intake of polyphenols from the usual diet. This controlled, human nutritional intervention investigated whether the enhancement of refined olive oil with orange peel extract may modulate postprandial lipemia, glycemia, and oxidative stress in individuals at cardiometabolic risk. In a cross-over framework, 21 participants aged 30–65 years, who met the eligibility criteria, received a fat and carbohydrate meal of mashed potatoes, homogenized with refined olive oil (50 mL) or the functional olive oil, enhanced with 10% orange peel extract, intervening a washout week. Blood draws were performed in fasting, 30 min, 1.5 h, and 3 h after the meal intake. Plasma lipids, glucose, uric acid, and total plasma antioxidant capacity, according to the FRAP method, were measured at each timepoint. A significant reduction of LDL-cholesterol was observed, 1.5 h and 3 h after the functional meal intake, compared to non-significant changes after the control meal (p < 0.05). No other statistically significant interactions were detected to the remaining biomarkers (p > 0.05). Further investigation is needed for safer conclusions about the postprandial modulation of cardiometabolic risk factors by the functional olive oil enhanced with orange peel extract.