The World's Healthiest Foods
Olive oil

Anyone coming from the Mediterranean region of the world would tell you about the health benefits, as well as the wonderful flavor, of a good dose of olive oil on salads, pasta, fish and almost anything else. Fortunately, it is available throughout the year to satisfy taste buds and promote good health.

Olive oil is made from the crushing and then subsequent pressing of olives. The fact that olives are rich in oil is reflected in the botanical name of the olive tree - Olea europaea as oleas means oil in Latin. Extra virgin olive oil is derived from the first pressing of the olives and has the most delicate flavor.

 


Health Benefits

Pure, extra virgin olive oil is not only a light and delicate addition to many wonderful dishes, it is one of the most health-promoting types of oils available. Olive oil is rich in monounsaturated fat, a type of fat that researchers are discovering has excellent health benefits. Just one ounce of extra virgin olive oil contains 86.2% of the daily value for monounsaturated fat, plus 17.4% of the DV for vitamin E, a fat-soluble antioxidant that protects these healthy fats from damage by free radicals.

Protection Against Chronic Degenerative Disease

In many parts of the world, a high fat intake is associated with degenerative diseases such as atherosclerosis, diabetes, asthma, colon cancer, and arthritis. But in some parts of the world, a high fat intake is actually associated with lower rates of these conditions. A closer look at the foods eaten in these places reveals that the high fat intake is actually due to the generous use of olive oil. Comparing these areas, such as the Mediterranean, where olive oil is the main fat used, to other regions, like the United States, where other fats such as animal fats, hydrogenated fats and vegetable oils like corn oil dominate, turns up some very interesting data. It turns out that people who use olive oil regularly, especially in place of other fats, have much lower rates of heart disease, atherosclerosis, diabetes, colon cancer, and asthma.

Heart Health

Studies on olive oil and atherosclerosis reveal that particles of LDL cholesterol (the potentially harmful cholesterol) that contain the monounsaturated fats of olive oil are less likely to become oxidized. Since only oxidized cholesterol sticks to artery walls, eventually forming the plaques that can lead to a heart attack or stroke, preventing the oxidation of cholesterol is a good way to help prevent atherosclerosis. A recent in vitro study also showed that polyphenolic compounds present in olive oil, including oleuropein, inhibit the adhesion of monocyte cells to the blood vessel lining, a process that is involved in the development of atherosclerosis. In addition, when people with high cholesterol levels removed the saturated fat from their diets and replaced it with olive oil, their total cholesterol levels dropped an average of 13.4%, and their LDL cholesterol levels dropped by 18%. Note, however, that these benefits occured when they used olive oil in place of other fats, rather than simply adding olive oil to a diet high in unhealthy fats.

A study published in the March 2004 issue of Medical Science Monitor reported that 2 tablespoons a day of olive oil added to an otherwise unchanged diet in 28 outpatients, ranging in age from 64 to 71, resulted in significant drops in total- and LDL cholesterol. Mean concentrations of total cholesterol were lowered by 0.818 mmol/L, and mean concentrations of LDL dropped 0.782 mmol/L. Plus, subjects ratio of HDL:LDL greatly improved; they ended up with higher amounts of protective HDL in relation to lower amounts of dangerous LDL cholesterol.

Three other recent studies (Valavanidis et al.; Morella et al.; Masella et al., see references below) suggest that such heart-healthy effects from olive oil are due not only to its high content of monounsaturated fats, but also to its hefty concentration of antioxidants, including chlorophyll, carotenoids and the polyphenolic compounds tyrosol, hydrotyrosol and oleuropein—all of which not only have free radical scavenging abilities, but protect the vitamin E (alpha-tocopherol) also found in olive oil.

Greek scientists at the University of Athens reporting their research in the April 2004 issue of the Journal of Agriculture and Food Chemistry believe the synergy of all these beneficial nutrients is what is responsible for olive oil’s contribution to the health benefits of the Mediterranean diet, a hypothesis supported by Italian research published in the April 2004 issue of the Journal of Nutrition.

In this study, scientists found that the phenols in olive oil have very potent antioxidant effects. The protective effects exerted by extra virgin olive oil biophenols, namely, protocatechuic acid and oleuropein, against LDL oxidation included:

  • completely preventing LDL’s oxidation when placed in a medium containing macrophage-like cells (in the arteries, arteriosclerosis begins when macrophages damage LDL, starting the development of foam cells that infiltrate the lining of the artery and begin plaque formation)
  • inhibiting the production of two powerful oxidants that would normally have been produced and would have damaged LDL, thus preventing the expected decrease in glutathione, a powerful antioxidant the body produces to disarm oxidants (also called free radicals)
  • restoring to normal levels the protective activities of two free radical-disarming enzymes that contain glutathione: glutathione reductase and glutathione peroxidase
  • inducing higher than normal production and activity of both of these glutathione-containing enzymes.


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 20,343 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. The authors concluded that olive oil intake alone may be as important as fruit and vegetables for the Mediterranean diet's beneficial effect on blood pressure.

Key to the Mediterranean Diet's Ability to Reduce Breast Cancer Risk

Olive oil may be the key reason that eating a Mediterranean diet reduces breast cancer risk, suggests a laboratory study published in the January 2005 issue of the Annals of Oncology. Oleic acid, the main monounsaturated fatty acid in olive oil, has been shown to reduce the expression of the Her-2/neu oncogene, which is associated with the aggressive growth of breast cancer tumors. High levels of Her-2/neu are found in one-fifth of breast cancers, especially those that are resistant to treatment. In this study, when Menendez and his colleagues from Northwestern University in Chicago exposed two strains of aggressive breast cancer cells to oleic acid, levels of Her-2/neu dropped 46%. When they combined oleic acid with lower levels than are normally used of Herceptin, a drug used to treat breast cancer, oleic acid greatly enhanced the effectiveness of the drug, dropping Her-2/neu expression as much as 70%. The end result: oleic acid promoted the apoptotic cell death (suicide) of aggressive, treatment resistant breast cancer cells.

Better Blood Sugar Control

Studies in diabetic patients have shown that healthy meals that contained some olive oil had better effects on blood sugar even than healthy meals that were low in fat. When olive oil is used to enhance a low-saturated fat, high carbohydrate diabetic diet, the diet still has beneficial effects on blood sugar control. In addition to this, a good diabetic diet with some olive oil added helps to keep triglyceride levels low. Triglyceride levels tend to be high in diabetic patients, which is a problem since high levels also contribute to the development of heart disease. So a high carbohydrate, healthy diabetic diet with some olive oil added in can help for several reasons.

Anti-Inflammatory Benefits

As far as other diseases go, regular use of olive oil has been associated with lower rates of asthma and rheumatoid arthritis. The monounsaturated fats in olive oil are used by the body to produce substances which are relatively anti-inflammatory. By reducing inflammation, these fats can help reduce the severity of arthritis symptoms, and may be able to prevent or reduce the severity of asthma.

Minor components of extra virgin olive oil—namely, its squalene, beta-sitosterol and tyrosol —may help explain why the Mediterranean diet has shown such beneficial effects on cardiovascular health and cancer prevention, suggests a study published in the November 2003 issue of Free Radical Biology and Medicine. It is generally accepted in the medical community that excessive production of free radicals and inflammatory compounds derived from the body’s use of omega 6 fatty acids (found primarily in meats, corn, safflower and sunflower oils) contributes to the development of both cardiovascular disease and cancer. In this study, researchers tested the effects of squalene, beta-sitosterol and tyrosol on a number of free radicals as well as on inflammatory compounds produced from omega 6 fats (arachidonic acid metabolites). In each case, the olive oil compounds either significantly inhibited production of the problem-causing molecules or rendered them harmless.

Protection Against Colon Cancer

Certain substances in olive oil have also been shown to be helpful for protecting the cells of the colon from cancer-causing chemicals. While most other fats are associated with an increased risk of colon cancer, olive oil is actually associated with a reduced risk of this disease.

One reason for olive oil's protective effect may be its ability to reduce the amount of carcinogenic heterocyclic amines (HAs) formed when meats are cooked, suggests a study published in the November 2003 issue of Food Chemistry Toxicology. The addition of foods containing antioxidants to recipes containing meat has previously been shown to decrease the amount of HAs produced during cooking. In this study, beefburgers were fried in both virgin and refined olive oils as well as virgin olive oil with rosemary extract and refined olive oil with rosemary extract. Burgers fried in virgin olive oil had significantly less HAs than those cooked in refined olive oil; however, the longer the oil was stored, the less its HA-reducing effect— a good reason to buy olive oil in small quantities that you will use within a month or two. Researchers theorized that adding rosemary to virgin olive oil might help prevent this drop in its protective effects.

Olive oil is definitely one of the best food oils available today. Simply adding olive oil to an unhealthy diet that is already soaked in saturated fats or vegetable oils will not lead to any of the benefits listed above and may actually cause more harm than good, but when pure, extra-virgin olive oil is used as a primary source of fat in a whole foods, healthy eating plan, the potential goodness of this oil prevails.].

A Fat That Can Help You Lose Fat
Substituting olive oil, a monounsaturated fat or MUFA, for saturated fat in your diet can translate into a small but significant loss of both body weight and fat mass without changing anything else about your diet or increasing your physical activity, suggests a study published in the September 2003 issue of the British Journal of Nutrition. One of the most interesting facts about this research is that it was conducted on eight overweight or obese men, ranging in age from 24 to 49 years. All the men followed one of two diets for 4 weeks each. The first, saturated fat-rich diet provided 24% of calories from saturated fat, 13% from monounsaturated fat, and 3% from polyunsaturated fat, while in the second MUFA-rich diet, 11% of calories came from saturated fats, 22% from monounsaturated fat and 7% from polyunsaturated fat. At the end of the MUFA-rich diet, despite the fact that no significant differences were detected in caloric intake, energy expenditure or physical activity, the men were 2.1 kg lighter and their fat mass had decreased by 2.6 kg.


Additional support for olive oil’s fat burning effects comes from a study published in the December 2003 issue of the British Journal of Nutrition, which suggests that the monounsaturated fats found in olive oil cause an increase in the breakdown of fats in fat cells (adipocytes). In this study, 45 rats were divided into three groups, each of which was fed a diet supplying normal energy but a different type of fat: olive oil, palmitic acid or soybean oil + palmitic acid. At the end of the study, a number of indicators of fat metabolism were measured including body weight, plasma leptin, tissue concentration of fatty acids, fat-cell size, fat cell lipolytic (fat breakdown) activity, and the capacity of insulin to inhibit fat breakdown. In the animals receiving monounsaturated fats, not only was fat breakdown greater, but insulin’s ability to block it was lower. Interestingly, in rats given polyunsaturated fat in the form of soybean oil, the opposite effect was noted in adipose (fat) tissue.

Description

Olive oil is made from the crushing and then subsequent pressing of olives. The fact that olives are rich in oil is reflected in the botanical name of the olive tree - Olea europaea as oleas means oil in Latin.

Olive oil is available in a variety of grades, which reflect the degree to which it has been processed. See How to Select and Store for more information on these different grades of olive oil.

History

Olives, one of the oldest foods known, are thought to have originated in Crete between five and seven thousand years ago. Since ancient times, the olive tree has provided food, fuel, timber and medicine for many civilizations, and has been regarded as a symbol of peace and wisdom. The venerable oil of the olive has been consumed since as early as 3,000 B.C.

Olives were brought to America by the Spanish and Portuguese explorers during the 15th and 16th centuries. They were introduced into California by the Franciscan missionaries in the late 18th century. Olive oil has been and still is a staple in the diet of many Mediterranean countries. The recent discovery that the Mediterranean diet, which features this prized oil, may be linked to a reduced risk of heart disease has caused olive oil to become very popular in the United States in the past few decades. Today, much of the commercial cultivation of olive oil is still centered in the Mediterranean region in such countries as Spain, Italy, Greece, Portugal and Turkey.

How to Select and Store

How to Enjoy

For some of our favorite recipes, click Recipes.

A Few Quick Serving Ideas:

Use olive oil in your salad dressings.

Purée roasted garlic, cooked potatoes and olive oil together to make exceptionally delicious garlic mashed potatoes. Season to taste.

Drizzle olive oil over healthy sautéed vegetables before serving.

Purée olive oil, garlic and your favorite beans together in a food processor. Season to taste and serve as a dip.

Instead of putting the butter dish out on the table, place a small cup of olive oil out instead to use on your bread or rolls. For extra flavor, try adding a little Balsamic vinegar or any of your favorite spices to the olive oil.

Safety

Olive oil is not a commonly allergenic food, is not included in the list of 20 foods that most frequently contain pesticide residues, and is also not known to contain goitrogens, oxalates, or purines.

Nutritional Profile

Introduction to Food Rating System Chart

The following chart shows the nutrients for which this food is either an excellent, very good or good source. Next to the nutrient name you will find the following information: the amount of the nutrient that is included in the noted serving of this food; the %Daily Value (DV) that that amount represents (similar to other information presented in the website, this DV is calculated for 25-50 year old healthy woman); the nutrient density rating; and, the food's World's Healthiest Foods Rating. Underneath the chart is a table that summarizes how the ratings were devised. For more detailed information on our Food and Recipe Rating System, please click here.

 

Extra Virgin Olive Oil
1.00 tbs
126.00 calories
Nutrient Amount DV
(%)
Nutrient
Density
World's Healthiest
Foods Rating
World's Healthiest
Foods Rating
Rule
excellent DV>=75% OR Density>=7.6 AND DV>=10%
very good DV>=50% OR Density>=3.4 AND DV>=5%
good DV>=25% OR Density>=1.5 AND DV>=2.5%

References

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  • Bond R, Lloyd DH. A double-blind comparison of olive oil and a combination of evening primrose oil and fish oil in the management of canine atopy. Vet Rec 1992 Dec 12;131(24):558-60.
  • Carluccio MA, Siculella L, Ancora MA et al. Olive oil and red wine antioxidant polyphenols inhibit endothelial activation antiatherogenic properties of mediterranean diet phytochemicals. Arterioscler Thromb Vasc Biol 2003 Apr 1; 23(4):622-9.
  • Ensminger AH, Esminger M. K. J. e. al. Food for Health: A Nutrition Encyclopedia. Clovis, California: Pegus Press; 1986.
  • Haban P, Klvanova J, Zidekova E, Nagyova A. Dietary supplementation with olive oil leads to improved lipoprotein spectrum and lower n-6 PUFAs in elderly subjects. Dietary supplementation with olive oil leads to improved lipoprotein spectrum and lower n-6 PUFAs in elderly subjects. Med Sci Monit. 2004 Mar 23;10(4):PI49-PI54.
  • Marrugat J, Covas MI, Fito M, Schroder H, Miro-Casas E, Gimeno E, Lopez-Sabater MC, De La Torre R, Farre M. Effects of differing phenolic content in dietary olive oils on lipids and LDL oxidation: A randomized controlled trial. Eur J Nutr. 2004 Jun;43(3):140-7. .
  • Martinez-Dominguez E, de la Puerta R, Ruiz-Gutierrez V. Protective effects upon experimental inflammation models of a polyphenol-supplemented virgin olive oil diet. Inflamm Res 2001 Feb;50(2):102-6.
  • Masella R, Vari R, D'Archivio M, Di Benedetto R, Matarrese P, Malorni W, Scazzocchio B, Giovannini C. Extra Virgin Olive Oil Biophenols Inhibit Cell-Mediated Oxidation of LDL by Increasing the mRNA Transcription of Glutathione-Related Enzymes. J Nutr. 2004 Apr;134(4):785-91.
  • Menendez JA, Vellon L, Colomer R, Lupu R. Oleic acid, the main monounsaturated fatty acid of olive oil, suppresses Her-2/neu (erbB-2) expression and synergistically enhances the growth inhibitory effects of trastuzumab (HerceptinTM) in breast. Ann Oncol. 2005 Jan 10; [Epub ahead of print].
  • Morello JR, Motilva MJ, Tovar MJ, Romero MP. Changes in commercial virgin olive oil (cv Arbequina) during storage, with special emphasis on the phenolic fraction. J Agric Food Chem, 2004 May; 85(3):357-364.
  • Moreno JJ. Effect of olive oil minor components on oxidative stress and arachidonic acid mobilization and metabolism by macrophages RAW 264.7. Free Radic Biol Med. 2003 Nov 1;35(9):1073-81.
  • Persson E, Graziani G, Ferracane R, Fogliano V, Skog K. Influence of antioxidants in virgin olive oil on the formation of heterocyclic amines in fried beefburgers. Food Chem Toxicol. 2003 Nov;41(11):1587-97.
  • Piers LS, Walker KZ, Stoney RM, Soares MJ, O'Dea K. Substitution of saturated with monounsaturated fat in a 4-week diet affects body weight and composition of overweight and obese men. Br J Nutr. 2003 Sep;90(3):717-27.
  • Psaltopoulou T, Naska A, Orfanos P, Trichopoulos D, Mountokalakis T, Trichopoulou A. Olive oil, the Mediterranean diet, and arterial blood pressure: the Greek European Prospective Investigation into Cancer and Nutrition (EPIC) study. Am J Clin Nutr. 2004 Oct;80(4):1012-8.
  • Soriguer F, Moreno F, Rojo-Martinez G, Garcia-Fuentes E, Tinahones F, Gomez-Zumaquero JM, Cuesta-Munoz AL, Cardona F, Morcillo S. Monounsaturated n-9 fatty acids and adipocyte lipolysis in rats. .Br J Nutr. 2003 Dec;90(6):1015-22.
  • Valavanidis A, Nisiotou C, Papageorgiou Y, Kremli I, Satravelas N, Zinieris N, Zygalaki H. Comparison of the Radical Scavenging Potential of Polar and Lipidic Fractions of Olive Oil and Other Vegetable Oils under Normal Conditions and after Thermal Treatment. .J Agric Food Chem. 2004 Apr 21;52(8):2358-65.
  • Visioli F, Romani A, Mulinacci N, et al. Antioxidant and other biological activities of olive mill waste waters. J Agric Food Chem 1999 Aug;47(8):3397-401.
  • Wood, Rebecca. The Whole Foods Encyclopedia. New York, NY: Prentice-Hall Press; 1988.

This page was updated on: 2005-02-11 16:09:38
© 2002 The George Mateljan Foundation