Olive oil is an oil obtained from the olive (Olea europaea; family Oleaceae), a traditional tree crop of the Mediterranean Basin. It is commonly used in cooking, cosmetics, pharmaceuticals, and soaps and as a fuel for traditional oil lamps. Olive oil is used throughout the world, but especially in the Mediterranean countries.
Nutrition and Health Effects
Olive oil Nutritional value per 100 g (3.5 oz)
- Energy – 3,701 kJ (885 kcal)
- Carbohydrates - 0 g
- Fat - 100 g
- saturated - 14 g
- monounsaturated - 73 g
- polyunsaturated - 11 g
- omega‑3 fat - <1.5 g
- omega‑6 fat - 3.5-21 g
- Protein - 0 g
- Vitamin E - 14 mg (93%)
- Vitamin K - 62 μg (59%)
*100 g olive oil is 109 ml
Percentages are relative to US recommendations for adults.
Olive oil contains a wide variety of valuable antioxidants that are not found in other oils. Hydroxytyrosol is thought to be the main antioxidant compound in olives, and believed to play a significant role in the many health benefits attributed to olive oil. Epidemiological studies suggest that olive oil has a protective effect against certain malignant tumours in the breast, prostate, endometrium and digestive tract. Research has revealed that the type rather than the quantity of fat seems to have more implications for cancer incidence.
Evidence from epidemiological studies also suggests that a higher proportion of monounsaturated fats in the diet is linked with a reduction in the risk of coronary heart disease. This is significant because olive oil is considerably rich in monounsaturated fats, most notably oleic acid.
In the United States, producers of olive oil may place the following health claim on product labels:
- Limited and not conclusive scientific evidence suggests that eating about 2 tbsp. (23 g) 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, olive oil is to replace a similar amount of saturated fat and not increase the total number of calories you eat in a day.
This decision was announced November 1, 2004, by the Food and Drug Administration after application was made to the FDA by producers. Similar labels are permitted for foods rich in omega-3 fatty acids such as Almonds and hemp seed.
There is a large body of clinical data to show that consumption of olive oil can provide heart health benefits such as favourable effects on cholesterol regulation and LDL cholesterol oxidation, and that it exerts antiinflamatory, antithrombotic, antihypertensive as well as vasodilatory effects both in animals and in humans. Additionally, Olive oil protects against heart disease as it controls the “bad” levels of LDL cholesterol and raises levels of the “good” cholesterol, HDL.
As they are the least processed forms of olive oil, extra virgin or virgin olive oil have more monounsaturated fatty acids than other olive oil. These types also contain more polyphenols, which may have benefits for the heart.
Some clinical evidence suggests that it is olive oil’s phenolic content, rather than its fatty acid profile, that is responsible for at least some of its cardioprotective benefits. For example, a clinical trial published in 2005 compared the effects of different types of olive oil on arterial elasticity. Test subjects were given a serving of 60 g of white bread and 40 ml of olive oil each morning for two consecutive days. The study was conducted in two stages. During the first stage, the subjects received polyphenol-rich oil (extra virgin oil contains the highest amount of polyphenol antioxidants like oleuropein or tyrosol). During the second phase, they received oil with only one fifth the phenolic content. The elasticity of the arterial walls of each subject was measured using a pressure sleeve and a Doppler laser. It was discovered that after the subjects had consumed olive oil high in polyphenol antioxidants, they exhibited increased arterial elasticity, while after the consumption of olive oil containing fewer polyphenols, they displayed no significant change in arterial elasticity. It is theorized that, in the long term, increased elasticity of arterial walls reduces vascular stress and consequentially the risk of two common causes of death—heart attacks and stroke. This could, at least in part, explain the lower incidence of both diseases in regions where olive oil and olives are consumed on a daily basis.
In addition to the internal health benefits of olive oil, topical application is quite popular with fans of natural health remedies. Extra virgin olive oil is the preferred grade for moisturizing the skin, especially when used in the oil cleansing method (OCM). OCM is a method of cleansing and moisturizing the face with a mixture of extra virgin olive oil, castor oil (or another suitable carrier oil) and a select blend of essential oils. Olive oil has been known for generations not only for its healing qualities but also as a natural, deep penetration moisturizer, regenerating skin cells and softening the tissue. Olive oil is also used by some to reduce ear wax buildup.
Olive oil can be used as an effective shaving oil to shave facial and other body hair.
Studies on mice showed that application of olive oil immediately following exposure to UVB rays has a preventive effect on the formation of tumors and skin cancer.
It is also widely used in cosmetics, soaps and are immensely beneficial in adding smoothness and softness to dry scaly skins especially during winter seasons.
Olive oil is unlikely to cause allergic reactions, and as such is used in preparations for lipophilic drug ingredients. It does have demulcent properties, and mild laxative properties, acting as a stool softener. It is also used at room temperature as an ear wax softener. Olive oil is also a potent blocker of intestinal contractions, and can be used to treat excessive Borborygmus.
Oleocanthal from olive oil is a non-selective inhibitor of cyclooxygenase (COX) similar to classical NSAIDs like ibuprofen. It has been suggested that long-term consumption of small quantities of this compound from olive oil may be responsible in part for the low incidence of heart disease associated with a Mediterranean diet.
Another health benefit of olive oil seems to be its property to displace omega-6 fatty acids, while not having any impact on omega-3 fatty acids. This way, olive oil helps to build a more healthy balance between omega-6 fats and omega-3 fats.
Unlike saturated fats, olive oil lowers total cholesterol and LDL levels in the blood. It is also known to lower blood sugar levels and blood pressure.
Olive oil contains the monounsaturated fatty acid oleic acid, antioxidants such as vitamin E and carotenoids, and oleuropein, a chemical that may help prevent the oxidation of LDL particles.
Preliminary research indicates that olive oil could possibly be a chemopreventive agent for peptic ulcer or gastric cancer, but confirmation requires further in vivo study. Olive oil was also found to reduce oxidative damage to DNA and RNA, which may be a factor in preventing cancer.
Unsaturated oils, such as olive oil, have a short shelf life and are prone to becoming rancid from oxidation, which will produce toxic byproducts and a bitter taste. Protection of unsaturated oils from heat and light will delay spoilage.
Source : http://www.wikipedia.org