Olive oil is one of the main ingredients of the Mediterranean diet, and it has been shown to lower death rates from cardiovascular disease in southern European countries. Consuming more than half a teaspoon of olive oil a day has been shown to lower heart disease risk. It has also been shown in a recent study to reduce the rate of premature death from cardiovascular disease and reduce Alzheimer disease, compared to people who never or rarely consumed olive oil.
Olive oil has the highest amount of monounsaturated fat, compared to other edible plant oils. Monounsaturated fat lowers the bad LDL cholesterol and increases the good HDL cholesterol. Olive oil also lowers the blood pressure and contains compounds that have anti-inflammatory and antioxidant properties, reducing disease process in general, and reducing heart disease in particular.
Olive oil is produced from the olive tree fruit, grown mainly in the Mediterranean area for over 5 thousand years, with Spain being the largest producer of olive oil in the world, followed by Italy and Greece. Spanish missionaries in the 18th century brought olives to California and they were planted along the coast. Currently in the United States, olive trees grow exclusively for oil production, in 40,000 acres in California, Florida, Georgia, Arizona, Hawaii and Oregon. About 90 million gallons of olive oil is produced in the U.S. but only 5% is consumed, according to the American Olive Oil Producers Association.
There are different grades of olive oil in the stores, ranging from regular olive oil to extra virgin olive oil (EVOO). In the Mediterranean diet, which is the healthiest dietary pattern and is emphasized by the American Heart Association to prevent heart disease, EVOO is the staple fat source. EVOO is the fatty part of the olive juice extracted only by mechanical and physical processes without any refinement. The lack of refinement maintains its sensory and healthy properties and is sometimes termed “first-press” or “cold-press”.
The regular olive oil has been refined, deodorized, bleached and mixed with 5 to 15% of EVOO. It is also labeled as “light” or “pure” reflecting a product that is lighter in flavor, color and smell.
The recommendation is that olive oil is a healthy substitute for margarine, butter and other types of fates. Other vegetable oils substitutes include sunflower, canola, soybean, corn and safflower oils. The EVOO has a strong flavor, and so it is best used to dress salads and vegetables, while canola oil is flavorless and can be used in baked food. It has to be noted that no single nutrient or food has much health impact compared to the whole dietary pattern. A Mediterranean diet or a variation of it is highly recommended.