It is quite interesting how research has shown that the people living in Mediterranean countries do not suffer from many of the coronary diseases of the rest of the world. Experts have attributed this to a simple trait, their diet. A Mediterranean diet, low in red meat, and high in fruits, vegetables, and olive oil seems to be the key to longevity and a healthy lifestyle.
When you go to the supermarket and stand in front of the oil displays, you may wonder which one to buy. Which is best? Frankly, most of the oils on those shelves are not useful in your diet; and, with the exception of some none are "good for you," despite advertising claims. All commonly used oils, with the exception of extra virgin olive oil, have been expelled with heat, (even if they are labeled "cold pressed"), bleached, and subjected to other processes that leave them empty of nutritional benefit.
One of the staples of a Mediterranean diet is cold pressed extra virgin olive oil, made from the first pressing of the choicest olives, and it is the one exception. In Greece, and other Mediterranean countries, where it is consumed in quantity, people have much lower blood cholesterol levels and a much lower rate of heart disease than people in the United States and Europe.
Many studies indicate that the health benefits of olive oil are attributed to the high level of monounsaturated fats in cold pressed olive oil which actually lower blood cholesterol levels. However, this is only true when the oil is cold pressed. Once heated, as in cooking, its quality and structure is altered. Extra virgin olive oil, which is cold pressed, is best. "Virgin" is usually obtained from the second pressing and is of a lesser quality. Avoid "Pure", as it is a blend of inferior oils and is not recommended.
When following a Mediterranean diet, you can use extra virgin olive oil on all your salads and on any dish that will not be heated. Use as a replacement for butter on potatoes, vegetables, and even on toast. When cooking, extra virgin is still preferred, but virgin is acceptable. I prefer the extra virgin and use it exclusively. There are many people, who are converting to a Mediterranean diet, that find the taste of olive oil unsuitable for all types of cooking. For those people, there are some very good replacement oils.
Sunflower, safflower, and corn oil are good substitutes for extra virgin olive oil when baking. Although unlikely to be found in a Mediterranean diet, these oils are lower in saturated fat than butter and have no cholesterol at all. When cooking in a wok, try sunflower, safflower, or light sesame oil for flavor. A good tip to avoid heat breakdown when you want to pan fry or saute is to place the food into the pan before adding the oil, then heat them together. Use less oil rather than more. A teaspoon of oil will go a long way.
Try to buy your olive oil in small quantities. Store in dark places, and always refrigerate after opening and, also keep any foods made with any oil refrigerated.