25 May

Of olives and oils

FROM the proverbial olive branch grows a small green (sometimes black) fruit. The essence of this fruit is in the oil, a pungent liquid of light green-golden colour, with a reputation that spans generations and cultures.

In ancient times, olive oil was revered as a gift of the gods, for people to use as food, lamp fuel, medicine, aphrodisiac and cosmetic. Today, olive oil has shed its mythical status, but it is no less important in the modern diet. 

“Olive oil is the only vegetable oil that can be consumed as it is” without further processing or refining, says Dr Yahya R. Laleli, founder of Laleli Olive Oil, who hails from Turkey, where olive groves dotting the landscape are a common sight.

The olive tree is native to countries that lie along the coast of the Mediterranean Sea, including France, Italy, Spain, Morocco, Greece and Egypt.

Olive oil has a special place in the Mediterranean diet, as it is believed to contribute to good health, not least in the prevention of heart disease.

“Olive oil is rich in monounsaturated fatty acids,” explains Dr Yahya, as well as contains omega-6 and omega-3, essential polyunsaturated fatty acids that can only be obtained from the diet.

While the monounsaturated and polyunsaturated fats play the lead roles in olive oil’s success story, there are also other beneficial compounds like beta-carotene, vitamin E, sterols and polyphenols, which contribute to the other effects of olive oil.

Health benefits

When it comes to the health benefits of olive oil, Dr Yahya, a solemn man who chooses his words carefully, comes as close as he ever will to gushing, during a recent talk organised by the National Heart Institute.

The most well known effect of olive oil is on heart health. Dr Yahya attributes it to the high oleic acid (a type of monounsaturated fat) content, which lowers “bad” LDL cholesterol while maintaining “good” HDL cholesterol.

He also quotes a study carried out by researchers from the Faculty of Medicine Timone in Marseille, France. The study, which was published in the American Journal of Clinical Nutrition, examined the diets of 212 volunteer subjects, all of whom had a moderate risk for heart disease.

“To investigate the value of a Mediterranean diet, subjects were split into two groups, one to consume a low-fat diet and the other to take a Mediterranean diet (rich in whole grains, fruit, olive oil, vegetables and red wine),” says Dr Yahya.

“Results found that those who had taken the low-fat diet reported a drop in cholesterol of 4.5%. The group who had consumed the Mediterranean diet had a cholesterol reduction of 7.5%,” which he explains is translated into a 15% reduction of heart disease risk.

Olive oil is also believed to protect against cancer, including breast, colon and prostate cancer, although there are no definitive studies that prove this, or demonstrate the mechanism of action.

Dr Yahya suggests that olive oil has a protective effect on age-related cognitive decline, and may even play a role in increasing longevity.

“A calorically-restricted diet – that includes all nutrients but has 30% fewer calories – has been found to extend the lifespan of rodents by 30 to 50%. Scientists hope, but do not yet know, whether the same will be true in people.

“One class of chemicals found to mimic calorie restriction is flavones, found abundantly in olive oil,” he explains.

Compared to other vegetable oils, olive oil ranks among the highest in terms of monounsaturated fatty acids, but loses out in the polyunsaturated fatty acids category.

However, Dr Yahya maintains that olive oil has the advantage, as it can be consumed as it is without refinery. Other oils have to undergo refinery, where the other benefits from the seed or plant, including plant sterols and phenolic compounds, are lost in the process.

Prized virginity

The quality of olive oil is measured by its “virginity” – in other words, whether the oil was extracted from the fruit without any chemical treatment or refining, which may lead to alterations in the oil.

As a result, you have extra virgin, virgin and pure (a blend of refined and virgin) olive oil. Interestingly, the level of virginity does not only refer to the oil’s physical characteristics, but also affects its beneficial properties.

For example, extra virgin olive oil is now known to have similar anti-inflammatory activity to the painkiller ibuprofen. The anti-inflammatory properties are due to a compound called oleocanthal, which is what produces the stinging sensation at the back of the throat when you consume extra virgin olive oil.

The discovery is said to be significant because scientists believe that inflammation plays an important part in a variety of chronic diseases like stroke, heart disease, and breast and lung cancer.

Even our senses can give us a clue to which olive oils are more beneficial. The organoleptic characteristics of olive oil, as perceived by our sense of smell and taste, are used to grade the quality of the oil.

“Mild bitter, pungent, fresh, aromatic and fruity tastes are some of the desirable traits associated with good organoleptic qualities. On the other hand, tastes of strong bitter, earthy, rancid or flat are undesired and are signs of inferior quality oil,” explains Dr Yahya.

Virgin and extra virgin olive oil have more organoleptic benefits, which translates into more health benefits.

In the end, the best olive oil is one that suits your taste and cooking style. If you are a “virgin” to cooking with olive oil, start with a mid-range “multi-purpose” oil and let the flavour transport you to the Mediterranean coast!
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