The Mediterranean diet with its high content of olive oil is well-documented to reduce cardiovascular disease and overall mortality.1-3
Scientists have discovered a range of beneficial compounds naturally found in extra virgin olive oil, depending on the brand selected.
Recent research shows that olive oil’s potent effects are dependent not only on its monounsaturated fatty acids, but also on constituents known as polyphenols. Levels of polyphenols vary with the source and method of olive fruit processing.
Compared to other food oils (corn, cottonseed, safflower, etc.), olive oil is more expensive. This has created a situation whereby olive oil is being diluted with cheaper oils to generate greater profits at the expense of public health.
As we found when investigating this scandal, a large percentage of products labeled as “extra virgin olive oil” are not what consumers think and some are outright counterfeit.4-6
Fortunately, a source of extra virgin olive oil has emerged that is tested to deliver high polyphenols—and to have zero adulteration or mishandling.
Researchers continue to confirm that those who follow a Mediterranean diet have a longer life expectancy and a lower risk of heart disease, high blood pressure, and stroke.1-3
Olive oil has built a strong reputation for defending against diabetes, cancer, rheumatoid arthritis, and other diseases. Newly released studies demonstrate that incorporating olive oil into one’s daily diet may protect against other conditions such as Alzheimer’s, osteoporosis, and skin aging as well as premature death.7-14
A 2013 study found that these benefits are greater when extra virgin olive oil is substituted for regular olive oil.15 This study found that many of the beneficial effects of the Mediterranean diet can be ascribed largely to the quality of its extra virgin olive oil.7
Results from a 2015 study point to the superiority of extra virgin olive oil for cooking. A comparison of different cooking methods found that the use of extra virgin olive oil for cooking not only preserved the antioxidants found in vegetables, it also boosted their content.16
Extra virgin olive oil is a rich source of monounsaturated fatty acids, along with various polyphenol compounds such as oleocanthal, oleuropein, hydroxytyrosol, and tyrosol.7 These substances are believed to modulate nearly 100 human genes8 that favorably control cell signaling9 and age-associated processes.7
The health benefits of olive oil consumption vary widely, however, depending on the choice of product. Those not consuming the right type or amount of olive oil might not be getting much benefit at all.
This is due to two problems. First is that the overall polyphenol content of any olive oil is inconsistent among brands. Second, most olive oil products on the market have been shown to be seriously adulterated.
Let’s delve into each of these two issues, which are critical to understanding biological effects of this remarkable oil.
Polyphenol Levels are Critical
Originally, olive oil’s high content of monounsaturated fatty acids was credited with its health benefits. Abundant levels of one particular monounsaturated fatty acid known as oleic acid have been demonstrated to increase high-density lipoprotein (HDL) or “good” cholesterol and decrease low-density lipoprotein (LDL) or “bad” cholesterol.17
Scientists initially thought that if oleic acid were responsible for the bulk of olive oil’s cardiovascular and other health benefits, they would see the same benefits with oleic acid itself. But that is not what they found.18
Instead, an explosion of research strongly suggests that many of olive oil’s benefits are attributable to its polyphenols, which are compounds naturally occurring that inhibit oxidation and extend shelf-life. The presence of disease-fighting polyphenols in olive oil appears to explain why other monounsaturated-rich oils don’t come close to matching olive oil’s health benefits.19
Hydroxytyrosol is one of the polyphenols found in the highest amounts in olive oil—and it has been demonstrated to provide key cardiovascular benefits.20,21 This polyphenol and others that are abundant in extra virgin olive oil—including tyrosol and verbascoside—neutralize free radicals, lower blood pressure, and slow atherosclerosis.21 Over 30 different polyphenols (also called phenolics) are found in extra virgin olive oil, including lignans and the secoiridoids known as oleuropein and oleocanthal.21,22
A recent meta-analysis, including 32 studies and 841,211 subjects, clarified that the benefits of olive oil consumption far exceed the benefits of other rich sources of monounsaturated fatty acids—underscoring that olive oil’s beneficial effects derive from polyphenols.23
This meta-analysis showed that when evaluating olive oil separately, olive oil itself reduced the risk for all-cause mortality by 23%, cardiovascular events by 28%, and stroke incidence by 40%. Monounsaturated fatty acid intakes that came from a general mix of animal and plant origins did not reveal any significant risk reduction for all-cause mortality, cardiovascular events, or stroke.23
As University of California at Davis scientists reported regarding this meta-analysis, extra virgin olive oil “… is the only oil that is high both in monounsaturated fat and phenol content, and comparable health benefits would not be provided by other oils or foods.”24
As a result, it is now broadly recognized that the high polyphenol content of extra virgin olive oil (not its high monounsaturated fat content) is an important driver of its documented reduction in cardiovascular disease risk and other benefits.18,19,23
Olive Polyphenols Regulate Blood Lipids
The amount of cholesterol in one’s blood and its breakdown of “bad LDL” and “good HDL” remains a hallmark by which conventional authorities assess vascular disease risk.
Olive oil favorably modulates these blood lipid levels.
A flurry of studies reveals differences between higher-polyphenol and lower-polyphenol olive oils for a variety of cardiovascular markers. Olive oils richer in polyphenols were found to produce:
- Reduced LDL,25
- Improved LDL density,25
- Increased HDL,26,27
- Improved HDL function,28
- Reduced LDL oxidation,26,29 and
- Improved postprandial hemostatic (blood flow-inhibiting) profile to a less thrombogenic (clot-promoting) state.30,31
These favorable changes in blood markers of cardiovascular risk show the value of ingesting lots of olive oil polyphenols.
What’s been overlooked until recently is the variation in polyphenol content among olive oil products on the market. A key study that measured levels of one particular polyphenol demonstrated that some olive oil brands on the United States market provide five times as much of this polyphenol as some others.32
In response to data indicating the importance of olive oil polyphenols, a specific source of extra virgin olive oil has been identified that contains consistently high levels of total polyphenols.
We’ll return to this exciting and potentially life-saving oil later. But first, let’s examine the other hurdle when it comes to deriving olive oil’s full benefits—rampant product adulteration.
Olive Oil Adulteration is Widespread
The United States is the world’s third-largest consumer of olive oil, and standards for the top grade—“extra virgin”—have been established by the International Olive Council and United States Department of Agriculture (USDA).33
However, there are numerous ways to cheat, and enforcement is virtually nonexistent. An estimated 50% of extra virgin olive oil brands sold in Italy—and 75% to 80% of extra virgin olive oil brands sold in the United States—do not even meet the legal grades to be called extra virgin.6
The most common fraud involves diluting extra virgin olive oil with lower-quality oils from North Africa and other areas. Worse, many bottles labeled extra virgin olive oil contain almost no olive oil at all—just a seed oil such as sunflower, altered with chlorophyll and beta-carotene to convey the same appearance and fragrance.6 Some use an inert liquid fat as a base, adding just a little olive oil to pass it off as genuine. Others deodorize rancid oil using chemicals and heat, killing off its health properties.34
In addition to laboratory measured standards for “extra virgin,” the International Olive Council and USDA have established sensory standards—indicators that detect when oils are oxidized, low-quality, lacking characteristic fruity flavor, or adulterated with cheap, refined oils.33
Using these sensory tests, University of California at Davis scientists analyzed 186 extra virgin olive oil samples from several countries, all selected randomly from retail shelves in California. They found that 73%—imported and local—failed. The extent to which each failing brand failed its sensory tests ranged from 56% to 94%. The majority of samples tested exhibited one or more of the following:33
- Oxidation by exposure to high temperatures, light, or aging,
- Adulteration with cheaper, refined olive oil, or
- Poor quality from processing flaws, improper storage, or use of damaged and overripe olives.
Experts advise consumers to check for the authentic fresh-fruity and spicy-peppery tastes, but how can people be fully certain that they’re unleashing the potency of the real thing?
Fortunately, our scientific investigators have identified a source that surpasses the lab measurement and sensory standards of pure, fresh, extra virgin olive oil—while delivering polyphenols at the highest end of the scale!
High-Polyphenol, Adulteration-Free Olive Oil
Refining causes a reduction in the polyphenol content of olive oil. Extra virgin olive oil is less refined.
Even among authentic extra virgin olive oils, a host of factors interact to determine polyphenol content. These include olive variety, weather type, timing of harvest, promptness of pressing, pressing method, handling, distance to market, and storage.32
An investigation has found an olive oil brand that is both polyphenol-packed and completely pure and unadulterated, making it possible for Americans to derive the full health benefits of extra virgin olive oil.
This is especially critical in light of research reporting that it is the polyphenol content of olive oils that unleashes the full health benefits, including reduction in all-cause mortality.18,23,25-31
This California-derived extra virgin olive oil meets all conditions for purity. The olives are grown on a family farm, providing the Mediterranean-like climate needed for nutrient-rich olives while avoiding the long transit time involved in importing Mediterranean-derived oil. The non-GMO olives are harvested early in the season and handpicked to exclude leaves and avoid the bruising caused by mechanical harvesters. They are crushed within hours of harvest rather than days, and the resulting oil is then cold-extracted and not filtered, which preserves its raw qualities, after which it is stored in temperature-controlled stainless steel tanks until it’s poured into dark bottles to protect it from light.
Summary
Olive oil’s beneficial effects are highly dependent on its polyphenols.
There are huge differences in polyphenol content of commercially sold olive oil brands. This can occur because of variable growing conditions and from extraction and handling differences.
Most troubling, however, is widespread adulteration. Studies show that between 75% and 80% of oils sold in the United States as “extra virgin olive oil” are adulterated or diluted.
A California grown extra virgin olive oil has been identified that is lab-tested to be superior in polyphenol content with no adulteration.
If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.
