Olive & Oil 31/07/2014

Not all extra virgin olive oils have so much health effects

Phenol enriched virgin olive oil improves human endothelial function. The benefits associated with polyphenol-rich olive oil consumption on cardiovascular risk could be mediated through an in vivo nutrigenomic effect in humans

Both oleic acid and polyphenols have been shown to increase high-density lipoprotein (HDL) cholesterol and to protect HDL from oxidation, a phenomenon associated with a low cholesterol efflux from cells. 

A Spanish research determines whether polyphenols from olive oil could exert an in vivo nutrigenomic effect on genes related to cholesterol efflux in humans.

In a randomized, controlled, cross-over trial, 13 pre/hypertensive patients were assigned 30 ml of two similar olive oils with high (961 mg/kg) and moderate (289 mg/kg) polyphenol content. 

Researchers found an increase in ATP binding cassette transporter-A1, scavenger receptor class B type 1, peroxisome proliferator-activated receptor (PPAR)BP, PPARα, PPARγ, PPARδ and CD36 gene expression in white blood cells at postprandial after high polyphenol olive oil when compared with moderate polyphenol olive oil intervention (P<.017), with COX-1 reaching borderline significance (P=.024). Linear regression analyses showed that changes in gene expression were related to a decrease in oxidized low-density lipoproteins and with an increase in oxygen radical absorbance capacity and olive oil polyphenols (P<.05). 

The results indicate a significant role of olive oil polyphenols in the up-regulation of genes involved in the cholesterol efflux from cells to HDL in vivo in humans. These results are in agreement with previous ones concerning the fact that benefits associated with polyphenol-rich olive oil consumption on cardiovascular risk could be mediated through an in vivo nutrigenomic effect in humans.

The additional health-promoting properties of functional virgin olive oil (FVOO) enriched with its own phenolic compounds (OOPC) versus the parental virgin olive oil (VOO) must be tested in appropriate human clinical trials. 

The aim of sicentists was to assess the effects of FVOO on endothelial function in hypertensive patients.

Thirteen pre- and stage-1 hypertensive patients received a single dose of 30 mL of FVOO (OOPC = 961 mg/kg) or VOO (OOPC = 289 mg/kg) in a postprandial randomised, double blind, crossover trial. Endothelial function, measured as ischemic reactive hyperemia (IRH) and related biomarkers, were followed for 5 h after consumption.

Compared with VOO, FVOO increased IRH (P < 0.05) and plasma Cmax of hydroxytyrosol sulphate, a metabolite of OOPC 2 h postprandial (P = 0.05). After FVOO ingestion, oxidised LDL decreased (P = 0.010) in an inverse relationship with IRH AUC values (P = 0.01).

FVOO provided more benefits on endothelial function than a standard natural virgin olive oil in pre- and hypertensive patients.


Rosa-M. Valls, Marta Farràs, Manuel Suárez, Sara Fernández-Castillejo, Montserrat Fitó, Valentini Konstantinidou, Francisco Fuentes, José López-Miranda, Montserrat Giralt, María-Isabel Covas, María-José Motilva, Rosa Solà, Effects of functional olive oil enriched with its own phenolic compounds on endothelial function in hypertensive patients. A randomised controlled trial, Food Chemistry, Volume 167, 15 January 2015, Pages 30-35

Marta Farràs, Rosa M. Valls, Sara Fernández-Castillejo, Montserrat Giralt, Rosa Solà, Isaac Subirana, María-José Motilva, Valentini Konstantinidou, María-Isabel Covas, Montserrat Fitó, Olive oil polyphenols enhance the expression of cholesterol efflux related genes in vivo in humans. A randomized controlled trial, The Journal of Nutritional Biochemistry, Volume 24, Issue 7, July 2013, Pages 1334-1339

di S. C.