Updated November 30th
What is blood pressure?
Blood pressure is a measure of the force that your heart uses to pump blood around your body. Blood pressure is measured in millimetres of mercury (mmHg) and is given as 2 figures: systolic pressure – the pressure when your heart pushes blood out; diastolic pressure – the pressure when your heart rests between beats. For example, if your blood pressure is “140 over 90” or 140/90mmHg, it means you have a systolic pressure of 140mmHg and a diastolic pressure of 90mmHg.
As a general guide, ideal blood pressure is considered to be between 90/60mmHg and 120/80mmHg. High blood pressure is considered to be 140/90mmHg or higher, low blood pressure is considered to be 90/60mmHg or lower.
High blood pressure is often related to unhealthy lifestyle habits, such as smoking, drinking too much alcohol, being overweight and not exercising enough. Left untreated, high blood pressure can increase your risk of developing a number of serious long-term health conditions, such as coronary heart disease and kidney disease.
Blood pressure and why it matters
Blood travels from the heart via arteries to smaller arterioles, then to capillaries or sinusoids, to venules, to veins and back to the heart. Blood pressure refers to the force pushing outward on the walls of your arteries. The more forcefully that the blood pumps, the more that the arteries are required to stretch to allow the blood to easily flow. Over time, if that force is too great, the tissue that makes up the arterial walls can become stressed and damaged.
This can lead a wide range of problems. For example, it makes arteries more vulnerable to infiltration and accumulation of cholesterol. It also can destabilize any existing arterial plaques which increases the risk of them rupturing and inducing heart attacks.
So, high blood pressure is a really big deal. High blood pressure is often characterized as a “silent killer” because it can cause permanent damage throughout the body without any obvious symptoms. Tragically, by the time the problem becomes obvious, it is sometimes too late to reverse the damage.
About 70 million adults in the US have hypertension – that’s 1 in every 3! and only around 52% of people with hypertension have it under control. It is also likely that many are walking around with the condition who don’t even know they have it.
Healthy blood pressure levels are an indicator of how clear the body’s arteries are. When blood pressure levels get out of balance, they can signal a potential heart attack or stroke. High blood pressure levels are often caused by atherosclerosis, also called hardening of the arteries, which occurs when oxidized particles of LDL cholesterol stick to the walls of the arteries. Eventually these particles build up and form plaque, narrowing the blood vessels and putting a heavier workload on the heart as it pumps oxygenated blood to the entire body.
How Does Extra Virgin Olive Oil Aid Blood Pressure
Due to minimal processing, extra virgin olive oil is the only oil that retains important natural phenols. Extra virgin olive oil is processed in a manner similar to many fruit juices: the fruit is crushed and the juice is extracted. In contrast, the other grades of olive oil (“pure” and “light”), as well as inexpensive oils such as soybean and canola, go through an industrial refining process that strips away phenols.
Extra virgin olive oil with a higher phenolic content may have a more robust flavour including some bitterness, than extra virgin olive oil with lower phenolic content. Phenolic content diminishes with time, and particularly when exposed to heat, light and oxidation, so extra virgin olive oil should be stored in a cool dark place and used within a couple months of opening a container.
One of the specific compounds in Extra Virgin Olive Oil that directly combats this build-up is called oleuropein. Oleuropein has been found by scientists to prevent the LDL cholesterol from oxidizing and sticking to the arterial walls.
Oleuropein is a natural phenolic compound found in olive leaves and green olives, including the olive’s skin and flesh, from which olive oil is transferred. It causes the bitter taste in Extra Virgin olive oil.
Health Benefits of Oleuropein
Oleuropein health benefits include anti-oxidant and natural anti-inflammatory activity, low blood glucose values and free radicals removal. In addition, oleuropein has been linked to cardioprotective and neuroprotective activity.
Oleuropein belongs to a group of coumarin derivative called secoiridoids. It was found to be effective against various strains of bacteria, viruses, fungi and also moulds or even parasites. Oral treatment with oleuropein results in a decreased number of blood vessels proving strong anti-angiogenic properties. Phenolic compounds (oleuropein, protocatechuic acid) in extra virgin olive oil have also been shown to inhibit macrophage-mediated LDL oxidation. Leaf and olive fruit extracts containing oleuropein protect insulin-producing β-cell line (INS-1) against the deleterious effect of cytokines.
Extra Virgin Olive Oil As Medicine
Studies On The Effect Of Extra Virgin Olive Oil On Blood Pressure
The following is a summary of seven studies carried out to examine the effect of extra virgin olive oil on blood pressure and hypertension. They conclude that extra virgin olive oil with a total phenol content of at least 161 mg/kg at a minimum intake of two tablespoons (25 ml) a day could significantly decrease systolic blood pressure in as little as three weeks. Extra virgin olive oil that contains at least 300 mg/kg total phenols may also decrease diastolic blood pressure.
In 2000, Ferrara published the first study that examined the effect of extra virgin olive oil on blood pressure. The study included 23 hypertensive men and women (age range: 25 to 70 years) and compared daily consumption of extra virgin olive oil to sunflower oil over six months The study found that extra virgin olive oil was more effective than sunflower oil in reducing both systolic blood pressure and diastolic blood pressure. In addition, 8 of the 23 participants were able to discontinue their hypertensive medications after six months of daily use of extra virgin olive oil.
Perona studied 62 elderly (mean age: 84 years) men and women in Spain, half of whom had hypertension, and compared four weeks each of 60 grams a day of extra virgin olive oil or sunflower oil. Systolic blood pressure was decreased to what the authors considered “normalized” (136 ± 10 mmHg) in the hypertensive participants after the extra virgin olive oil phase, compared to the sunflower oil (150 ± 8 mmHg).
In a study by Rozati of 41 overweight (BMI 29 ± 1 kg/m2 ), but otherwise healthy adults, three months daily intake of extra virgin olive oil compared to 49 grams day of a corn and soybean oil combination lowered systolic blood pressure, but there was no difference between the oils for diastolic blood pressure.
Fito, studied 40 men (mean age = 67) with coronary heart disease, 19 of whom had hypertension, and compared refined olive oil (ROO) containing very little phenols to extra virgin olive oil with a moderate total phenol content (161 mg/kg total phenols) for three weeks of daily consumption. The extra virgin olive oil phase significantly decreased systolic blood pressure for the hypertensive participants compared to the ROO phase (mean difference for extra virgin olive oil compared to ROO = -2.53 mmHg). However, neither of the oils had a significant impact on diastolic blood pressure.
In contrast, the EUROLIVE (Effect of Olive Oil Consumption on Oxidative Damage in European Populations) study (Castaner) found that total phenol content may have an impact on diastolic but not systolic blood pressure. The study compared refined olive oil ROO to extra virgin olive oil with a moderately high total phenol content of 366 mg/kg at 25 ml/day for three weeks in 18 healthy men. The study found that compared to the ROO, the high total phenol extra virgin olive oil reduced diastolic blood pressure, but neither oil had a significant impact on systolic blood pressure.
Another key study found that extra virgin olive oil with a high total phenol content may reduce both systolic and diastolic blood pressure. Moreno-Luna, studied 24 young women classified with high-normal blood pressure (120-139/80-89 mmHg) or Stage 1 essential hypertension (140-159/90-99 mmHg) who consumed extra virgin olive oil with 564 mg/kg total polyphenol or ROO for eight weeks each.
Compared to the ROO, the extra virgin olive oil decreased systolic blood pressure and diastolic blood pressure. It is noteworthy that this study showed that high phenol extra virgin olive oil was more effective in reducing blood pressure than the reductions reported from the DASH study (Dietary Approaches to Stop Hypertension), which required consuming close to nine servings per day of fruits and vegetables to lower systolic blood pressure by 2.8 mmHg and diastolic blood pressure by 1.1 mmHg.
There is also a study that found that extra virgin olive oil could provide blood pressure reduction to those who do not typically eat a Mediterranean diet. Bondia-Pons studied 160 men from Northern Europe, Central Europe, and Mediterranean countries.
The study required the consumption of 25 mL of three olive oils with three levels of phenols, with each oil consumed for three weeks. Although the changes in blood pressure were compared only after all three phases were completed, and not after each of the oils individually, the results showed a significant three percent decrease in systolic blood pressure in the non-Mediterranean subjects, while there was no change in the Mediterranean subjects. In addition, the poststudy blood pressure of the men from the non-Mediterranean countries was found to be similar to the lower baseline values of the men from the Mediterranean countries.