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Is Your Olive Oil Counterfeit?

September 2016

By Michael Downey

Is Your Olive Oil Counterfeit?  

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.

What You Need to Know
The Benefits of Extra Virgin Olive Oil

The Benefits of Extra Virgin Olive Oil

  • Scientists are finding varying cardiovascular benefits from extra virgin olive oil, depending on the brand tested.
  • Olive oil’s potent effects have now been shown to be dependent on its levels of constituents known as polyphenols.
  • Vast differences in polyphenol levels are due to extraction and handling differences, as well as to widespread adulteration of olive oil products. Up to 80% of oils sold in the US as extra virgin olive oil are adulterated.
  • Fortunately, an extra virgin olive oil has been identified that is tested to be vastly superior in polyphenol content as well as 100% adulteration-free.

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

The Vascular Protective Effects of Olive Oil Polyphenols
The Benefits of Extra Virgin Olive Oil

Recent focus on the link between extra virgin olive oil’s polyphenol content and its potent health effects has cast new light on its cardiovascular benefits—highlighting the critical impact of the polyphenols.

Higher-polyphenol olive oil shows a better ability to boost beneficial HDL cholesterol.26

A human crossover study provided the first direct evidence that high-polyphenol olive oil enhances HDL function. A three-week intake of 25 ml/d (about 1.7 tablespoons) of high-polyphenol olive oil produced a 3.05% increase in what is known as cholesterol efflux capacity, while a low-polyphenol olive oil produced only a 2.34% decrease.28 Cholesterol efflux capacity is a measure of how well HDL cholesterol removes bad cholesterol from white blood cells (macrophages) so that it can be eliminated from the body, reducing overall cholesterol.35 Another human trial revealed that olive oil polyphenols enhance the expression of genes that trigger this process.36

High-polyphenol olive oil was also shown to make HDL particles bigger, enhancing their ability to remove cholesterol from arterial plaque.28

A group of researchers found that 2 tablespoons of high-polyphenol olive oil daily for four months substantially improved endothelial function in adults with atherosclerosis.37 Endothelial dysfunction interferes with arteries’ ability to maintain healthy blood flow and normal blood pressure.38

In another human study, scientists determined that a higher polyphenol intake over one year, as a result of increased extra virgin olive oil consumption, decreased blood pressure in participating adults aged 55 to 80. Higher polyphenol intake, confirmed by increased urine polyphenol excretion, was linked directly to increases in plasma nitric oxide, which signals blood vessels to relax and thus lower blood pressure.39

Beyond cardiovascular effects, the polyphenols in extra virgin olive oil have been found to suppress cancer.40,41 For instance, the major extra virgin olive oil polyphenols have been shown to cause cells with the breast cancer-promoting gene HER2 to self-destruct.41

Although not specifically tied directly to polyphenols, olive oil also quells inflammation, protects stomach health, and inhibits other diseases—including Alzheimer’s and premature death.7-14

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.

What Are Polyphenols?
The Benefits of Extra Virgin Olive Oil

Polyphenols are naturally occurring compounds found largely in fruits, vegetables, tea, wine, and cocoa. They are secondary metabolites of plants, generally defending them against ultraviolet radiation or aggression by pathogens. More than 8,000 polyphenolic compounds have been identified in various plant species.42

The polyphenolic content of foods is greatly affected by environmental factors such as soil type, sun exposure, and rainfall. The degree of ripeness considerably affects the concentrations and proportions of polyphenols. A critical factor affecting polyphenol content of any food is storage time and type, which affects polyphenol oxidation. Exposure to light, heat, or air can destroy polyphenols.43

Polyphenols are anti-inflammatory and free-radical scavengers. Some have anticarcinogenic and cardioprotective effects. Polyphenols have beneficial effects on the endothelial lining of blood vessels by increasing the availability of nitric oxide and by preventing the lipid oxidation underlying atherosclerosis.

Numerous studies suggest that polyphenols from different plants may work synergistically to protect against cardiovascular disease, cancer, diabetes, endothelial dysfunction, osteoporosis, and neurodegenerative and other chronic diseases—without any known side effects.42

The typical Western diet lacks sufficient amounts and variety of plant polyphenols to be of optimal benefit.

Polyphenols give extra virgin olive oil its unique fresh-fruity and spicy-peppery taste and improve its shelf life, with some versions containing several times the polyphenols of others. So potent are these compounds that, cooking with extra virgin olive oil not only fully preserves the antioxidant value of the food, it also boosts the food’s antioxidant content.

Do you want to know what polyphenols “feel” like? Take a slow sip of extra virgin olive oil and wait for the sudden tingling at the extreme back of the throat. This is the tell-tale sign of an extra virgin olive oil that’s polyphenol-rich.

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!

Cooking and Storage Conditions for Extra Virgin Olive Oil
Cooking and Storage Conditions for Extra Virgin Olive Oil

There is a great deal of confusion amongst consumers as to what is the best oil to cook with. In order to make the best decision, we need to discuss two things: first, smoke point, or the temperature at which an oil begins to break down, loses its taste and nutritional benefits and releases harmful chemicals, and second, the tendency to oxidize or go rancid.

There’s a general belief that regular olive oil isn’t an optimal oil for sautéing due to having a low smoke point. But high quality extra virgin olive oil has a high smoke point of 400ºF. If olive oil in general has gotten a bad rap for use in cooking, it’s probably because up to 80% of the oils sold in the US as extra virgin olive oil are counterfeit. Most people who think they’re using it are actually using inferior oils.

The low acidity of high quality extra virgin olive oil allows it to have a longer shelf life since it tends to oxidize more slowly.44,45 Even so, proper storage conditions are important in order to minimize oxidization. Accordingly, high quality extra virgin oil should be kept in a cool, dark place and in a dark bottle away from light, oxygen, and heat as these factors can reduce the nutritional value of the oil in the long run. Cooking with genuine, unadulterated high quality extra virgin olive oil presents no problem for general cooking.

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.

New Analysis Highlights the Cardiac Dangers of Corn Oil

Over thirty years ago, Life Extension® identified corn oil, which is loaded with the omega-6 fatty acid linoleic acid, as pro-inflammatory.

The journal The BMJ (formerly The British Medical Journal) published a recently rediscovered clinical data set from between 1968 and 1973, with a study population of more than 9,000 people.46

Control subjects were fed saturated-fat rich meals that included red meat, milk and cheese. The intervention group had most of their saturated fats replaced by corn oil rich in the pro-inflammatory omega-6 fatty acid linoleic acid. The goal of the analysis was to evaluate the theory that omega-6 rich corn oil would protect people against heart disease and lower their mortality. What the researchers found, however, was that the use of corn oil to replace saturated fats in the diet lowered cholesterol but increased the risk of death from heart disease.

This new analysis of old data validates what Life Extension pointed out over thirty years ago, when we warned the public to select vegetable oils with care in order to avoid the pro-inflammatory omega-6 fatty acids like linoleic acid found in corn oil and other high omega-6 vegetable oils.

Heart-healthy vegetable oils with low amounts omega-6 linoleic acid and low saturated fat are far better options than corn oil rich in omega-6 linoleic acid.47 Whenever possible, be sure to look for extra virgin, cold pressed in order to receive the full benefits of these healthy oils. For salad dressings, olive oil and flaxseed are reasonable options. Flaxseed oil should always be refrigerated, and should never be used for frying. For sautéing, olive oil is a far better choice than corn oil.48

  • Extra virgin olive oil contains oleic acid and is rich in heart-healthy polyphenols including oleuropein, hydroxytyrosol, tyrosol, and verbascoside.17,20,21
  • Avocado oil, rich in monounsaturated fatty acids, carotenoids, and phytosterols is a healthy option.49
  • Flaxseed oil, high in healthy omega-3, alpha-linolenic acid is another healthy option.50

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.

Impact on Body Weight

A new study published in the journal Lancet Diabetes & Endocrinology lends further credence to the sterling reputation of extra virgin olive oil and its remarkable benefits for health and weight loss.51

In a randomized, controlled study, scientists analyzed the waist circumference and weight of 7,447 subjects who consumed three different diets over five years. They concluded that a Mediterranean diet, in which extra virgin olive oil is heavily featured, is more conducive to weight loss than low-fat diets. The findings held true for a variety of different groups, including those with type II diabetes, the elderly and people who are overweight or even obese.

Subjects were divided into three groups. One group had a Mediterranean diet featuring extra virgin olive oil, the second group had a Mediterranean diet that featured a mix of nuts, and the third group was instructed to simply avoid all fats. In the end, the olive oil group lost the most weight—an approximate two pounds, while the low-fat group averaged a 1.3-pound loss. The group that ate a Mediterranean diet with nuts lost an amount comparable to the low-fat group.

What may not be appreciated by this study is that adults tend to gain significant weight as they age. The fact that those who consumed the most extra virgin olive oil lost weight over a 5-year period makes it clear that olive oil is the type of fat to consume for those concerned about body weight.

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