Olive Oil: Health Benefits

In this Article (Index)

Health Benefits of of Olive Oil

• A History of Olive Oil
• Olive Trees
• How is Olive Oil obtained?
• Grades of Olive Oils
• Chemistry of Olive Oil
• Olive oil components & your health
• Olive Oil Health benefits
• The Mediterranean Diet
• Adding Olive Oil to your diet

Olive Oil a Nutraceutical

An Ancient History as food and medicine

The History of Olive Oil

Olive oil and olives have been used for millennia as a source of food. Olive oil was also recognized for its health benefits and incorporated into cosmetics and medicine.

Greek pharmacologist, botanist and physician Pedanius Dioscorides (c. 40–90 AD) is known as "the father of pharmacognosy." He wrote about olive oil in his medical encyclopedia De materia medica (1) describing its dietary and medical properties mentioning that olives just befoe their maturity produced the healthiest olive oil, calling them omphá it was fragrant and could also be used to make perfumes.
The older and more greasy oil was to be used for medicine he wrote that "in general, every [olive] oil is warming and softening the flesh, protecting the body from excessive cold and refreshing to work. It also has the ability to open body and soften."

Olive Trees, the source of olives and olive oil

Olive trees (Olea europaea L.) originated in the Mediterranean region in Europe, Asia, and Africa. It has spread around the globe and can be found in America, South America, Australia and South Africa.

It is an evergreen shrub or tree, short and wide that can grow to a height of about 25 to 50 ft (8 - 15 m). It is well adapted to dry and temperate climates.

The olive tree produces a rounded fruit, a drupe, called olive. The fleshy drupe has a diameter of around 3⁄8 to 1 3⁄16 in. (1.5 to 3 cm). It is green in summer and turns light red in autuymn.

Olives are composed of a thin, protective skin or epicarp surrounding the fleshy mesocarp that has a high content of edible olive oil. Then is the inedible stony endocarp surrounding the seed or pit.

The name, Olive

The tree, fruit and oil get their name from the Latin word oliva that means "fruit of the olive tree". It originated from the Classic Greek "ελαια" meaning "olive fruit" and "olive tree". The word for "oil" in Latin was oleum and it meant "olive oil" and in Greek, "ελαιον" that also means "olive oil".

How is Olive Oil obtained

Olive oil is extracted from the olives by a cold pressing method. It is a mechanical process that crushes the oily pulp and separates the oil from the pomace using water and centrifugation. It does not employ heat, cooking, or chemical solvents to extract the oil. The words "Extra Virgin" "Virgin" or "First Cold Pressed" olive oil reflect the purity of this process.

Just for the record, other oils such as corn, soybean, sunflower, and rapeseed (canola®) are extracted using solvents distilled from mineral oil such as hexane, a relative of gasoline. This process leaves hexane residues in the vegetable oil in very small proportions: less than 5 parts per million. So they are in comparison to olive oil not as natural.

The traditional oil pressing process is thousands of years old. Modernized in its equipment it still follows the ancient steps:

The olives are taken from the olive trees either by hand picking or knocking the branches without rods harming them.
The olive drupes are separated from the leaves and washed with water.
The olives are then milled by grinding and crushing to produce an oily paste.
In the past milling was followed by a malaxation process that churned the paste by slow grinding. This released more oil. However the friction heated the oil slightly to 80°F (27°C) and it also oxidized the lipids promoting the loss of antioxidants in the oil reducing its quality. This step is now avoided as it does not allow the resulting olive oil to be labelled as "cold extracted".

The oil-pomace paste is washed and an oil-water mixture is obtained; from which the olive oil is separated by centrifugation.

Grades of Olive Oils

There are many grades but the best ones carry the word "Virgin" in their name. This ensures optimal flavor and properies. These two grades are the Extra Virgin and the Virgin olive oil, that differ in their acidity level:

• Extra virgin olive oil or EVOO: it is obtained solely by mechanical processes, without heat that may alter the oil. The only treatments are : washing, decantation, centrifugation and filtration. Its content of oleic acid (acidity) does not exceed 0.8%
• Virgin olive oil or VOO: the same as above, but with a higher acidity (0.8 to 2%)

The Lampante olive oil is the lowest quality virgin olive oil. It is unfit for consumers as it has a poor smell or taste due the low quality olives or bad processing of the oil. It must be refined to make it fit for human use. The refining process removes these defects but the resulting "Refined olive oil" has no taste, color or aroma so it is blended with EVOO or VOO to make it an olive oil labelled as "Olive oil composed of refined olive oil and virgin olive oils". It may not have all the health properties of the Virgin grades, but are good for cooking, frying, broiling and are, in my opinion better alternatives than solvent extracted oils (corn, rapeseed, sunflower, soybean oil).

Refined olive pomace oil

Refined olive pomace oil is another secondary oil obtained after cold pressing olives, from the pulp or olive pomace. It is of inferior quality in comparison to EVOO or VOO. Its production may involve the use of solvents, which is the standard production method for obtaining edible oils from peanuts, corn, sunflower, soybean or rapeseed oils. It is probably better than other vegetable oils because it is monounsaturated fat and has more stability when used to cook for long periods of time as it resists oxidation better.
After refining it is blended with EVOO or VOO to make it fit for being marketed to consumers
Pomace has been found to contain antioxidants but in a lower concentration than the Virgin olive oil grades. We recommend sourcing pomace oils made in the European Union, where strict residual solvent levels are strictly monitored and regulated (5).

The Chemistry of Olive Oil

Olive oil is a blend of many kinds of fatty acids or lipids. Its mainly composed of monounsaturated fatty acids or MUFAs such as oleic acid (70-80% of the fat content in olive oil), and palmitic acid (10-11% ).
The oil contains smaller quantities of polyunsaturated fatty acids (PUFAs) such as linoleic acid (5-7%) and some saturated fatty acids (SFAs) in smalller amounts such as arachidic acid (less than 0.5%).

Until recently the beneficial health effects of olive oil were attributed to its monounsaturated fatty acid (MUFA) component, but there are over 200 bioactive chemical compounds present in the oil representing only 1-2% of the total oil, but they are potent botanical phytochemicals.

These compounds include carotenoids, sterols, and phenolic compounds. These minor components of olive oil have bioactive properties and act as antioxidants. For instance the hydrophilic phenols that are the most abundant antioxidants in the oil.
Another potent antioxidant is hydroxytyrosol (HT) ((3,4-Dihydroxyphenyl)ethanol) a polyphenol that is found in extra virgin olive oil (EVOO) and red wine, both of them form part of the Mediterranean Diet.

Current scientific belief is that these minor components and not the MUFAs, contribute to the healthy characteristics of olive oil.

These antioxidants are not found in other types of seed or grain oils (7) (8)

Positive health effects of Olive Oil's Components

We list below the health effects asociated to olive oil's bioactive components:

• Antioxidant activity. The phenolic content of the oil has protective effects, in particular the main polyphenol in Extra Virgin olive oil, hydroxytyrosol, is a potent antioxidant that reduces oxidized LDL type cholesterol and platelets aggregations protecting the heart (4). Antioxidants provide anti-inflammatory effects when olive oil is included in a regular diet(5). The antioxidants in EVOO also limit the risk of liver damage, and stop steatohepatitis (fatty-liver) (3).
• Antimicrobial effects against bacteria involved in respiratory and intestinal infections due to the presence of hydroxytyrosol, tyrosol, and oleuropein (6).
• Immune system boosters, plant polyphenols improve the immune system by affecting the white blood cell proliferation, as well as by the synthesis of cytokines and other factors, which contribute to immunological resistance (3).
• Anti-inflammatory. Oleuropein is an anti-inflammatory molecule and Oleocanthal exerts anti-inflammatory properties similar to ibuprofen (4).

The benefic properties of olive oil

The Mediterranean Diet

The Mediterranean Diet or MedDiet is inspired in the traditional food of the Mediterranean region, from Crete, Greece, Italy and Spain.
Its principal features are its balanced content of healthy foods: whole grains, legumes, fruits, vegetables and of course olive oil; moderate intake of fish, dairy products -consisting mainly of cheese or yogurt, limited beef and eggs intake and very moderate consumption of red wine.

Olive oil is the main source of lipids and the main aspect of the MedDiet; in this context, The III International Conference on Virgin Olive Oil and Health held in Jaen, Spain, issued a Consensus Report 2018 whose main points we highlight below: (2).

• Weight Loss: "There are sufficient studies reporting that the use of virgin olive oil as the only culinary fat, ingested in a moderate and continuous way, was associated with a reduced body mass index."
• Hypertension as a risk factor for heard disease: "The available randomized trials indicate that virgin olive oils reduce blood pressure and thus, the global cardiovascular burden of disease and its associated pharmaceutical costs."
• Heart protector: "Virgin olive oils have anti-atherosclerotic potential, favoring endothelial function and preserving blood pressure, maintaining lipoprotein functionality, exerting anti-inflammatory and antioxidant effects, and modulating gene expression in several tissues to maintain proper homeostasis."
• Preventing cancer (Chemoprevention): "Epidemiological studies ... support that a diet where virgin olive oils are the foremost source of fat is associated with chemoprevention. Animal studies are suggestive of a preventive effect of olive polyphenols... and it adds that The Mediterranean diet and virgin olive oils are associated with a lower risk and pevention of postmenopausal breast cancer.
  "The Mediterranean diet has also been suggested to reduce the risk of colorectal cancer", they also stat etath "we have no strong clinical evidence to support that they can affect the long-term progression of pre-malignant or cancerous lesions after diagnosis (treatment)."
• Autoimmune diseases: Clinical trials have confirmed a "significant anti-inflamatory and immunomodualtory effects of dietary virgin olive oils ... in preclinical models of autoimmune diseases, such as inflammatory bowel disease, rheumatoid arthritis, systemic lupus erythematosus and sclerosis. Thus, the consumption of virgin olive oil and its minor constituents may acquire a great importance in nutritional therapy, especially in immunocompromised patients."

Olive oil also protects the liver through the antioxidants that limit the risk of liver damage, and stop steatohepatitis (fatty-liver) and the oleic acid acid "contributes to the liver recovery from a steatotic process" (3).

Adding Olive Oil to your diet

Adding Extra Virgin Olive Oil (EVOO) to your salads is a good option, use it with salt, pepper, vinegar or lemon to dress your salads. It is much healthier than processed dressings you can find on the shelves in the supermarkets.

Replace saturated fats like cream or butter with olive oil in mashed potatoes, baked potato dressing instead of butter and sour cream, or on a slice of bread like they do in Greece, Italy or Spain: dip it in olive oil!

Drizzle onto cooked fish, meat, grilled, steamed or roasted veggies, over poached eggs, or creamy soup. Add it to your hummus, drizzle onto boiled potatoes.

Bake with it; traditional Mediterranean olive bread, focaccia and biscotti are baked with olive oil. Replace butter or other vegetable oils for olive oil. Bake your Muffins, banana bread, carrot cake, chocolate cake or gingerbread cake with it. Replace 1 tsp of butter for 3⁄4 tsp of olive oil or 1 cup of butter for ⁄4 cup of olive oil.

Replace your regular oil when frying an egg or cooking. It will be healthier and tasty.

Cooking with Extra Virgin Olive Oil and preserving its antioxidants isn't easy. Frying and steaming can preserve the antioxidants' potency while pressure cooking, boiling, microwaving or sautéing cause a signifcant drop in antioxidant content.

Healthy Tip

When boiling or using a pressure cooker note that the phenolic antioxidants are washed into the cooking water from the EVOO and the vegetables so using this water in your recipe, will incorporate those antioxidants back into the dish (4).

Compared to other oils, olive oil remains stable at higher temperatures over longer periods of time, than other oils and it resists the oxidation process that breaks down compounds in the oil, producing free radicals and trans-fatty acids.

Closing Comments

Olive oil is a natural plant oil, obtained by traditional cold press mechanical methods without using heat or solvents. This ensures it has a high content of potent bioactive botanical antioxidants.
It can be a healthy addition to your diet and you can even start with olive oil on your journey to adopt the Mediterranean Diet.
Olive oil has protective effects for heart, liver, cancer, and immune disorders. It is an anti-inflamatory, antimicrobial and can help you lose weight.