Olive oil has long been popular for both cooking and seasoning in Mediterranean countries. These days, however, it's being rediscovered in America. The low frequency of heart disease among those living in Mediterranean countries, despite lifestyles similar to more industrialized nations, has made us look more closely at their diets. The Mediterranean diet is lower in saturated fat than the typical American diet, but the total fat content can range from under 30 percent of calories to more than 40 percent of calories, which is considered high by American dietary guidelines. A distinctive difference between the two diets is the amount of monounsaturated fat in the Mediterranean diet.
The heavy use of olive oil by people living in that part of the world is the source of the high level of monounsaturated fat in their diets. Olive oil is rich in oleic acid, the most common monounsaturated fatty acid found in the diet. Numerous studies indicate that monounsaturated fat is about as effective as polyunsaturated fat in lowering total blood cholesterol and LDL cholesterol, when substituted for saturated fat in the diet. Plus, monounsaturated fat does not lower beneficial HDL cholesterol or raise triglycerides, unlike polyunsaturated fat, which, at high intakes, may lower HDL cholesterol.
The Food and Drug Administration allows manufacturers of olive oil to claim that "limited but not conclusive evidence suggests that eating about two tablespoons of olive oil daily may reduce the risk of coronary heart disease due to the monounsaturated fat in olive oil." Despite this qualified health claim, keep in mind that regardless of the type of oil you use, all oils have the same amount of calories -- 120 per tablespoon. To avoid weight gain, watch your portion size, and use oil in place of -- not in addition to -- other fats in your diet.
Olive oil, vegetable oils, fruits, and vegetables all contain plant sterols and stanols. To find out how these compounds can help lower blood cholesterol, see the next page.