Olive oil: A major player in the prevention of heart disease
Although the health and longevity of the Mediterranean people are associated with an authentic Mediterranean diet high in plant foods and low in animal products, what has really defined this traditional diet is the abundant use of olives and olive oil, the principal fat source and the culinary foundation of the Mediterranean cuisine.
For centuries, olive oil has been a major organic olive oil player in the low incidence of heart disease among Mediterranean populations. Extensive research has shown that olive oil not only can prevent damage to the arteries but can also reverse high levels of cholesterol in the blood and lower high blood pressure, a major risk for strokes.
In a study conducted by Montoya and associates, the participants followed four types of diets for a five-week period: One diet was rich in saturated fats; one in polyunsaturated fat (sunflower oil); one in monounsaturated fat (extra virgin olive oil); and the last one in omega-3 fatty acids from fish. The study showed that when people followed the diet rich in extra virgin olive oil, their levels of bad cholesterol went down and their blood pressure decreased 5 to 6 percent.1
We know that extra virgin olive oil is an irreplaceable source of fat when it comes to the heart because the main fat in olive oil is monounsaturated, the fat that does not get stuck in the arteries. We also know that all olive oils have about the same proportion of monounsaturated fat. Then, why buying extra virgin olive oil when it is more expensive than refined olive oil? Two major reasons:
1. Refined olive oils are loaded with chemicals
Thousands of years ago, the olives were crushed by hand in spherical stone basins; today, in a similar method, olives (with pits) are pounded and crushed using mechanical techniques. The oil produced in such a way (cold) is the extra virgin olive oil, the natural juice from the olives. It preserves the unique flavor, smell, and healthy properties of the fruit.
The solid residue that remains after the first extraction is sent back to the press to be beaten again and be exposed to different heat levels and chemical procedures. It is neutralized with sodium hydroxide, passed through charcoal filters, and extracted with hexane at low temperatures. The resulting oil lacks color and aroma, and has lost most of its antioxidant properties. That’s why these second extractions are not recommended for consumption. With time, the use of oils that have been subjected to chemical agents may have a toxic effect on our bodies.
2. Extra virgin olive oil contains more antioxidants than their refined versions
Countless studies conducted to examine the activities of some minor compounds in olive oil have indicated that they are strong antioxidants and potent free radical scavengers. Free radicals are highly unstable and destructive molecules that subject our cells to oxidative stress, continuous damage that eventually kills the cells. When radicals kill or damage enough cells in an organism, the organism ages and eventually dies. The antioxidants in olive oil are found in larger amounts in extra virgin olive oil than in refined olive oils. Let’s take a look at some of them.
o Vitamin E (±-tocopherol). Olive oil contains alpha-tocopherol or vitamin E, the tocopherol with the highest natural antioxidant activity and one of the most effective defenders against oxidation in our cell membranes. Consistent evidence shows that people with low levels of vitamin E in the blood have more damage in the arteries than people with an adequate amount.1 On average, the amount of vitamin E in the oil is about 24 to 43 milligrams for each 100 grams of oil.2 A tablespoon of extra virgin olive oil contains 1.6 milligrams (2.3 IU [International Units]) of vitamin E, providing 8 to 15 percent of the recommended daily intake.
o Polyphenols: tyrosol and hydroxytyrosol. Extensive research shows that polyphenols are potent antioxidants and inhibitors of free radical “attacks.” Tyrosol is quite stable and is able to undo oxidation of LDL cholesterol.3 Hydroxytyrosol is an efficient trash picker of free radicals and it contributes to the shelf life of the oil, delaying its auto-oxidation.4 Based on some studies,5 on average, these compounds in olive oil account for the following approximate levels: