Virgin Olive Oil the Best Oil for Heart Health
Virgin olive oil, a much richer source of polyphenols than refined olive or other refined oils, is the best vegetable oil for heart health, shows the results of the Eurolive study, published in the September 2006 Annals of Internal Medicine.
The 6 research center study, led by Maria-Isabel Covas of the Municipal Institute of Medical Research in Barcelona, assigned 200 healthy men from 5 European countries - Spain, Denmark, Finland, Italy and Germany - to one of three sequences of daily consumption of olive oil. The men replaced their normal dietary fats with olive oil (25 mL) containing either 2.7 (refined), 164 (virgin), or 366 (extra virgin) mg/kg of phenols for 3 weeks. This was followed by 2 weeks without any olive oil and then a cross-over to each of the other 2 remaining interventions.
Blood samples were taken before and after each intervention to measure blood sugar, total and HDL (good) cholesterol, triglycerides, free radical damage to cholesterol, and antioxidant levels.
The data revealed a linear increase in HDL (good) cholesterol levels as the phenolic content of the olive oil increased, with increases of 0.025, 0.032, and 0.045 mmol/L for the low, medium and high polyphenol-containing olive oils.
Oxidized LDL (the form in which LDL is involved in atherosclerosis) decreased linearly, dropping from 1.21 U/L , to -1.48 U/L , to -3.21 U/L for the low-, medium-, and high-polyphenol olive oil, respectively. And the ratio of total to HDL cholesterol, considered the most specific cholesterol-associated risk factor for cardiovascular disease, also decreased linearly as the phenolic content of the olive oil rose.
"Olive oil is more than a monounsaturated fat. Its phenolic content can also provide benefits for plasma lipid levels and oxidative damage," concluded the researchers.
A statement released by the Municipal Institute of Medical Research noted, 'This study represents a key piece for recommendations and contributes information with great repercussions for the community, especially in populations or countries where olive oil does not comprise the habitual oil of the diet."
Extra virgin olive oil-organic, if available-may cost a bit more than lesser quality oils, but the significant increase in cardiovascular benefits, not to mention richer flavor it provides, make it an extremely good investment in your health.
Key to the Mediterranean Diet's Ability to Lower Blood Pressure
Theodora Psaltopoulou and colleagues from the University of Athens, Greece investigated whether the Mediterranean diet as a whole, or just olive oil, is responsible for the reduction in blood pressure associated with this way of eating. Their finding: while the diet as a whole reduces blood pressure, olive oil, by itself, is largely responsible. The Greek team examined the ability of the total diet and of olive oil alone to reduce arterial blood pressure. Their study included over 20,000 Greek participants who were free of hypertension (high blood pressure) when the study began. Food frequency questionnaires were completed and systolic and diastolic blood pressures were taken.
Diet was evaluated by a 10 point score that reflected the extent to which study participants followed the Mediterranean diet and also provided scores for individual components of the diet, including olive oil.
Data analysis confirmed that the Mediterranean diet as a whole was significantly associated with lower systolic and diastolic blood pressure as were olive oil, vegetables and fruit. On the other hand, consumption of cereals, meat and meat products, and alcohol intake was associated with higher blood pressure. When the effects of olive oil and vegetables were compared, olive oil was found to be responsible for the dominant beneficial effect on blood pressure.
Polyphenols, not Fats, Responsible for Olive Oil's Benefits
It's likely the abundance of polyphenols in extra virgin olive oil, rather than its monounsaturated fatty acids, are responsible for its well-known cardiovascular benefits.
And its rich supply of polyphenols, which are known to have anti-inflammatory, antioxidant and anticoagulant actions, may also be central to emerging evidence that olive oil's protective effects extend to colon cancer and osteoporosis (see Protection against Colon Cancer, Olive Oil Polyphenols Prevent Bone Loss also in this section).
Research conducted by Dr. Juan Ruano and colleagues at the Reina Sofia University Hospital, Cordoba, Spain, and published in the Journal of the American College of Cardiology, investigated the effects of virgin olive oil on endothelial function in 21 volunteers with high cholesterol levels.
The endothelium, although just a one-cell thick layer of flat cells that lines the inner wall of all blood vessels, may be the critical player in cardiovascular health. Among its many functions, the endothelium orchestrates the mechanics of blood flow, and regulates blood clot formation and the adhesion of immune cells to the blood vessel wall (one of the first steps in the formation of plaque).
Normally, after a meal, endothelial function is impaired for several hours. Blood vessels become less elastic, and blood levels of free radicals potentially harmful to cholesterol (lipoperoxides and 8-epi prostaglandin-F2) rise.
But when the subjects in this study ate a breakfast containing virgin olive oil with its normal high phenolic content (400 ppm), their endothelial function actually improved, blood levels of nitric oxide (a blood vessel-relaxing compound produced by the endothelium) increased significantly, and far fewer free radicals were present than would normally be seen after a meal.
When they ate the same breakfast containing the same type of virgin olive oil with its phenolic content reduced to 80 ppm, the beneficial effects were virtually absent, and concentrations of cholesterol-damaging free radicals increased.
The results of this study underscore the importance of knowing how to select, store and serve your olive oil to maximize its polyphenol content. For all the information you need, see our How to Select and Store section below.
Olive Oil Makers Win Approval to Make Health Claim on Label
By MARlAN BURROS
November 2, 2004 WASHINGTON, Nov. 1 - The Food and Drug Administration said Monday that producers of olive oil could say on their labels that there was evidence that people could reduce the risk of coronary disease by replacing saturated fats in their diets with olive oil. Producers will now be able to say on their labels: "scientific evidence suggests that eating about two tablespoons (23 grams) of olive oil daily may reduce the risk of coronary heart disease due to the monounsaturated fat in olive oil. To achieve this possible benefit, Extra virgin olive oil is to replace a similar amount of saturated fat and not increase the total number of calories you eat in a day."
Olive oil's health benefits (Healingdaily.com)
The greatest exponent of monounsaturated fat is olive oil, and it's is a prime component of the Mediterranean Diet. Olive oil is a natural juice which preserves the taste, aroma, vitamins and properties of the oil fruit. Olive oil is the only vegetable oil that can be consumed as it is freshly pressed from the fruit.
The beneficial health effects of olive oil are due to both its high content of monounsaturated fatty acids and its high content of antioxidative substances. Studies have shown that olive oil offers protection against heart disease by controlling LDL ("bad") cholesterol levels while raising HDL (the "good" cholesterol) levels. No other naturally produced oil has as large an amount of monounsaturated as olive oil-mainly oleic acid. Olive oil is very well tolerated by the stomach. In fact, olive oil's protective function has a beneficial effect on ulcers and gastritis. Olive oil activates the secretion of bile and pancreatic hormones much more naturally than prescribed drugs. Consequently, it lowers the incidence of gallstone formation.
Olive oil and heart disease
Studies have shown that people who consumed 25 milliliters (ml)-about 2 tablespoons-of virgin olive oil daily for 1 week showed less oxidation of LDL cholesterol and higher levels of antioxidant compounds, particularly phenols, in the blood.( 4) But while all types of olive oil are sources of monounsaturated fat, EXTRA VIRGIN olive oil, from the first pressing of the olives, contains higher levels of antioxidants, particularly vitamin e and phenols, because it is less processed. Olive oil is clearly one of the good oils, one of the healing fats. Most people do quite well with it since it does not upset the critical omega 6 to omega 3 ratio and most of the fatty acids in olive oil are actually on omega-9 oil which is monounsaturated.
Super Food for the Heart
A review of the research by noted olive oil researcher Maria Covas strongly suggests that diets in which olive oil is the main source of fat can be a useful tool against a wide variety of risk factors for cardiovascular disease. (Covas MI, Pharmacology Research)
On November 2004, the Federal Drug Administration (FDA) of the U.S.A permitted a claim on olive oil labels concerning: "the benefits on the risk of coronary heart disease of eating about two tablespoons (23 g) of olive oil daily, due to the monounsaturated fat (MUFA) in olive oil."
But recent studies have shown that olive oil contains much more than MUFA. Olive oil is a functional food that is also rich in antioxidants and phenolic compounds with a variety of protective effects.
The cholesterol of a person whose diet is high in olive oil will primarily contain oleic acid, the fatty acid that predominates in olive oil, and oleic acid is more resistant to free radical or oxidative damage. And not only will the LDL of a person whose dietary fat is primarily olive oil produce LDL that is more resistant to free radical damage, but that individual's LDL will be firther protected by olive oil's supplies of vitamin E and phenols with antioxidant activity, further lessening the likelihood of its being oxidized.
By reducing both inflammation and free radical damage to cholesterol, dietary olive oil protects the endothelium, the lining of our blood vessels, helping to maintain its ability to relax and dilate (thus preventing high blood pressure).
By protecting LDL against oxidation, olive oil short circuits the process through which atherosclerotic plaques form. (Only once oxidized does LDL adhere to the endothelium, attracting immune cells (monocytes) that try to clear it out, turn into foam cells and begin plaque formation.)
The anti-inflammatory effects of a virgin olive oil-rich diet also result in a vascular environment in which platelets are less likely to clump together and form blood clots. Not only do olive oil's antioxidant compounds lessen the inflammation initiated by free radical damage, but olive oil is rich in inhibitors of a compound called platelet activating factor (PAF). PAF begins the clotting process by causing platelets to aggregate and is also involved in the activation of immune cells and their binding to the endothelial wall.
Compared to diets high in saturated fat and low fat, high carbohydrate diets, a number of studies have shown that olive oil-rich diets not only reduce LDL cholesterol levels, but also lower blood sugar levels and decrease insulin requirements in persons with type 2 diabetes.
Practical Tip: Rely on delicious, flavorful virgin olive oil as your first choice for dressing salads. Put a little olive oil and balsamic vinegar on your bread plate and use it to add flavor to crusty whole wheat bread and rolls. Drizzle olive oil over potatoes, beans, grains, steamed vegetables, and soups. You will not only enhance the flavor of your food, but greatly reduce your cardiovascular disease risk.