Health Effects of Consuming Olive Pomace Oil (ORUJOSALUD-2)

Differential Study of the Health Effects of Olive Pomace Oil in Healthy and at Risk Consumers in Comparison With Sunflower Oil

Healthy and at risk (hypercholesterolemic) subjects consumed during 4 weeks 45 g/d of either olive pomace oil (OPO) or sunflower oil (SO) as the only dietary fat in a randomized, crossover trial. The effects on blood lipids, glucose homeostasis, endothelial function, inflammatory cytokines, oxidative stress biomarkers and anthropometry were measured.

The intervention aimed at studying the potential health effects of olive pomace oil in comparison with sunflower oil. After a 3-weeks run-in, 31 healthy (normocholesterolemic) and 37 hypercholesterolemic subjects were randomized to consume either OPO or SO (45 g/d) during 4 weeks, followed by a 3-week wash-out during which volunteers consumed the same amount of corn oil. During all the study, other dietary sources of fat (oil, nuts, butter, etc.) were restricted. Food intake was monitored by 3-d food records in each intervention stage and volunteers were instructed to maintain their normal physical and dietary habits (except for the changes in the consumption of other oils and fats). At the beginning and end of each intervention stage, blood and urine samples were obtained, and blood pressure and anthropometric measurements were performed. A complete batch of analysis were performed, including serum lipids, endothelial function (endothelial nitric oxide synthase (eNOS), vascular (VCAM-1) and intercellular (ICAM-1) cell adhesion molecules, E- and P-selectins), inflammatory and anti-inflammatory cytokines, glucose homeostasis/insulin resistance, antioxidant status and biomarkers of lipid oxidation (malondialdehyde (MDA), LDLox, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) quenching capacity) and anthropometry, along with determination of incretins, adipokines, and other clinical and hematological parameters.

Olive pomace oil, Lipaemia, Glucose homeostasis, Inflammation, Oxidative stress biomarkers, Endothelial function

After a 3-week run-in, healthy and at risk (hypercholesterolemic) volunteers were randomly allocated to one of each arm. Each intervention stage lasted 4 weeks and was separated by a 3-week wash-out.

Volunteers consumed during 4 weeks 45 g/d of olive pomace oil as the only source of dietary fat, used for cooking, salad dressing, toasts, etc.

Volunteers consumed during 4 weeks 45 g/d of sunflower oil as the only source of dietary fat, used for cooking, salad dressing, toasts, etc.

Reduction of total or LDL-cholesterol levels or triglycerides in at risk (hypercholesterolemic) subjects. No effect on blood lipids expected in healthy (normocholesterolemic) volunteers

Modification of fasting blood glucose or insulin levels, decrease in glycosylated hemoglobin (Hb1Ac), homeostasis model assessment (HOMA) of insulin resistance (HOMA-IR) or beta-cell function (HOMA-beta)

Inclusion Criteria: Healthy volunteers (Total cholesterol < 200 mg/dL; LDL-cholesterol < 135 mg/dL) Hypercholesterolemic volunteers (Total cholesterol 200-300 mg/dL; LDL-cholesterol 135-175 mg/dL) Exclusion Criteria: BMI > 30 Kg/m2 Smokers Vegetarians Pregnant women Medication/consumption of vitamins, dietary supplements On antibiotic treatment 3 months before starting the study Digestive disorders/pathologies (gastric ulcer, Chron's disease, inflammatory bowel syndrome, etc.) Food allergies/intolerances