Consuming High-Polyphenol EVOO Reduces Blood Pressure, Study Finds

Researchers in Australia have demon­strated that con­sum­ing extra vir­gin olive oil that is high in polyphe­nols led to a ​“sig­nif­i­cant reduc­tion” in two dif­fer­ent types of blood pres­sure.

Peripheral and cen­tral sys­tolic blood pres­sure decreased in study par­tic­i­pants by 2.5 and 2.7 mil­lime­ters of mer­cury (mmHG), respec­tively. However, the researchers found that no sig­nif­i­cant dif­fer­ences were observed in dias­tolic blood pres­sure or arte­r­ial stiff­ness.

“The prac­ti­cal health impli­ca­tions of our study are focused on the fact that the addi­tion of just 60 mil­li­liters (about four table­spoons) of extra vir­gin olive oil in the daily diet can lead to a decrease in sys­tolic pres­sure that is of great clin­i­cal sig­nif­i­cance and pub­lic health impor­tance, espe­cially with regards to the pre­ven­tion of car­dio­vas­cu­lar dis­ease,” George Moschonis, a co-author of the study and asso­ciate pro­fes­sor at La Trobe University, told Olive Oil Times.

Moschonis added that the results of this study are par­tic­u­larly sig­nif­i­cant as a pre­vi­ous study pub­lished in the Lancet demon­strated that a 10 mmHg reduc­tion in sys­tolic blood pres­sure led to a 20 per­cent reduc­tion in car­dio­vas­cu­lar dis­ease, 17 per­cent decrease in coro­nary heart dis­ease, 27 per­cent reduced risk of stroke and 28 per­cent decrease in heart fail­ure.

However, most par­tic­i­pants in that study were already over­weight and achieved the reduc­tion in sys­tolic blood pres­sure via phar­ma­co­log­i­cal meth­ods.

Moschonis said that what stood out about the more recent study was the role extra vir­gin olive oil could play in low­er­ing blood pres­sure in healthy indi­vid­u­als.

“Contrary to the stud­ies included in this meta-analy­sis [the one pub­lished in the Lancet], our inter­ven­tion study was con­ducted with healthy par­tic­i­pants, did not include any med­ica­tion and did not require any weight loss or other major lifestyle mod­i­fi­ca­tions,” he said.

“The only change that our study intro­duced was the addi­tion of 60 mil­li­liters of raw extra vir­gin olive oil in par­tic­i­pants’ diet, indi­cat­ing that a small and eas­ily incor­po­rated change in the diet can pro­duce sig­nif­i­cant decreases in blood pres­sure even in healthy indi­vid­u­als, thus high­light­ing the value of extra vir­gin olive oil in the pri­mary pre­ven­tion of car­dio­vas­cu­lar dis­ease,” Moschonis added.

In the study, 50 par­tic­i­pants were divided into two groups. In one group, par­tic­i­pants con­sumed a daily dose of 60 mil­li­liters of a high-polyphe­nol (with a phe­no­lic con­tent of 360 mil­ligrams per kilo­gram) extra vir­gin olive oil for three weeks. In the other group, par­tic­i­pants con­sumed the same amount of refined olive oil, which is low in polyphe­nols (86 mil­ligrams per kilo­gram).

After the three weeks, the par­tic­i­pants spent two weeks cleans­ing their sys­tems, not eat­ing any olives or olive oils, before switch­ing over to con­sume the other type of olive oil.

Blood pres­sure read­ings on each of the par­tic­i­pants were taken after each of the three week peri­ods. What researchers found is that par­tic­i­pants only expe­ri­enced the periph­eral and cen­tral sys­tolic blood pres­sure decrease after con­sum­ing high-polyphe­nol extra vir­gin olive oil.

Neither type of blood pres­sure sig­nif­i­cantly decreased in either set of par­tic­i­pants after con­sum­ing the refined, low-polyphe­nol olive oil.

In the future, Moschonis said he hoped to repli­cate the study using indi­vid­u­als at higher risk of car­dio­vas­cu­lar dis­ease.

“The decrease in blood pres­sure lev­els could pos­si­bly be expected to be higher if the tar­get pop­u­la­tion were patients or indi­vid­u­als with a high car­dio­vas­cu­lar dis­ease risk, but this will be the focus of future research,” he said.

Moschonis added that the results of this study hold spe­cific impor­tance in Australia, where the country’s Health Star Rating System grades olive oil with three to 3.5 stars out of five, depend­ing on its qual­ity.

By com­par­i­son, both canola and sun­flower oil have higher rat­ings, which advo­cates of the sys­tem attribute to their lower sat­u­rated fat con­tent.

“Our study pro­vides new evi­dence that jus­ti­fies and fur­ther sup­ports the need for the revi­sion of Australia’s national Health Star Rating sys­tem, in order to also take into con­sid­er­a­tion the proven health ben­e­fits of bioac­tive nutri­ents in foods, such as the polyphe­nols in olive oil and specif­i­cally in extra vir­gin olive oil where the con­cen­tra­tion of polyphe­nols is higher,” Moschonis said.

“Unfortunately, in its cur­rent for­mat the national Health Star Rating sys­tem is based only on a hand­ful of nutri­ents in foods, such as their con­tent in sat­u­rated fat, while other ben­e­fi­cial nutri­ents are com­pletely ignored,” he added.