Extra virgin olive oil is one of the few oils that can be eaten without chemical processing (nearly every other vegetable oil has been refined with steam and solvents). Fresh pressed olive oil can be ingested immediately and retains the natural flavours, vitamins, minerals, antioxidants and other healthy products of the ripe olive fruit. Most doctors advocate lowering total fat and calories in your diet and substitute butter, margarine and tropical oils with healthy fats like olive oil ( The Olive Oil Source ).

What is Cholesterol?

Cholesterol is a fatty substance contained in foods of animal origin. Diets containing a large amount of animal fat raise blood cholesterol levels, which is one of the primary risk factors of cardiovascular disease.

Fats (triglycerides) and cholesterol are transported in the blood by lipoproteins. The cholesterol bound to low-density lipoproteins (very low density lipoproteins -VLDL and low-density lipoproteins -LDL) is artherogenic, damaging the vessel walls. In subsequent stages, this may lead to acute heart attack. Such cholesterol is known as "Bad cholesterol". In contrast, the cholesterol bound to high-density lipoproteins (HDL cholesterol) is called "Good cholesterol", because it provides protection against the onset of cardiovascular diseases. The high-density lipoproteins (HDL) remove free cholesterol from the cells, then esterifying it and transporting it to the liver, where it is eliminated with bail. That's why it is important to have high HDL-levels and low LDL-levels for your cholesterol.

Cholesterol and Olive Oil

Olive oil lowers the levels of total blood cholesterol, LDL-cholesterol and triglycerides. At the same time it does not alter the levels of HDL-cholesterol (and may even raise them), which plays a protective roll and prevents the formation of fatty patches, thus stimulating the elimination of the LDL-cholesterol.

The beneficial effect of olive oil consumption with regard to cardiovascular disease has been demonstrated in primary prevention, where it reduces the risk of developing the disease, and in secondary prevention, where it prevents recurrence after a first coronary event.

At present research is revealing the effectiveness of the Mediterranean diet in the prevention of secondary coronary events and the positive influence of olive oil on the depression associated with such events and on mood. These findings are very important in view of the high incidents of depression in the modern-day world and the great risk it poses in recurrent heart disease ( The International Olive Oil Council www.internationaloliveoil.org ).

Does Olive Oil contain Omega-3 and Omega-6 Fatty Acids?

Olive oil contains both omega-3 and -6 fatty acids. Omega-3 fatty acids are important in preventing cardiovascular disease and are particularly high in oily fish such as salmon. According to the Merck Manual, an authoritative medical text, essential fatty acids should make up 1-2% of the dietary calories for adults with a suggested ratio of 10:1 for omega-6: omega-3 fatty acids.

Olive oil is about 10% linoleic acid (an omega-6 fatty acid) and about 1% linolenic acid (an omega-3 fatty acid); therefore the ratio in olive oil is 10:1. "The perfect ratio for the human body."

If you were using only olive oil for your dietary fat and fats represented 30 % of the calories in your diet, then you would be getting 3% of your calories in the form of essential fatty acids in a 10:1 ratio, just as recommended.

What are Antioxidants and Oxidative stress?

Oxidation is a process that occurs not only when oil is pressed, but also inside our own bodies. Reactions occur continually inside the body, giving rise to the formation of free radicals (peroxidants). As a rule, free radicals do not cause severe damage thanks to the protection provided by antioxidants, which help to keep a balance up to a point. If the balance is spoilt, however, "oxidative stress" occurs, leading to deterioration of normal cell functions and even cell death.

Oxidation is a complex, fundamental phenomenon in the process of cell ageing. Lipid or fat peroxidation (free radicals) tends to be proportional to the number of double bonds in a compound, explaining why oleic acid shows little susceptibility to oxidation.

Cell membranes contain a large amount of fat and cholesterol and their composition depends on diet. When the diet contains a lot of olive oil, the cells are more resistant to oxidation, the do not deteriorate as much and ageing is slower.

Approximately 1,5% of olive oil is made up of the unsaponifiable fraction, which contain antioxidants. Virgin olive oil contains the largest quantities of these substances and other miner components.

Antioxidants in Olive Oil

Vitamin E (alpha-tocopherols), carotenoids and phenolic compounds (simple phenols such as hydrocytyrosol and complex phenols such as oleuropein =the bitter component in olives) are all antioxidants whose activity has been demonstrated in vitro and recently in vivo, revealing further advantages in the prevention of certain diseases and also of ageing.

The phenolic content of olive oil varies according to the climatic conditions in the producing area, when the olives are harvested and how ripe they are when picked. Oil production and storage methods also have an influence. Phenols have countless biological properties, for intance hydroxytyrosol inhibits platelet aggregation and it is anti-inflammatory and oleuropein encourages the information of nitric acid, which is a powerful vasodilator and exerts a strong anti-bacterial effect.

Oxidised LDL's are known to be athrogenic, which is where olive oil steps in, because it has a beneficial protective effect against LDL oxidation. Moreover, it also strengthens other cells in the body against the toxic effects of oxidants.

The high anti-oxidant content of the Mediterranean diet appears to contribute significantly to each effect on longevity.

These anti-oxidants are found in fresh fruit and vegetables, because it is the only oil to be obtained from fruit, olive oil retains a host of substances, anti-oxidants and vitamins that give it added nutritional value.

The Antioxidant Activity of Polyphenols has shown promising results with respect to:

Atherosclerosis

Oxidised LDL contributes to the progression of human atherosclerosis. Antioxidants have been shown to prevent LDL modification. The beneficial effects of a Mediterranean diet may be defined by the unique antioxidant properties of its phenolic compounds.

Cancer

There is a growing body of evidence that reactive oxygen species are involved in the etiologie of fat-related neoplasm, especially in patients suffering from predisposing inflammatory conditions where high quantities of reactive oxygen are produced. Recent studies have shown that the abundant phenolic antioxidant fractions of olive oil have a potent inhibitory ability on reactive oxygen species associated with colon and breast pathologies.

Oxidative stress from passive smoking

Recent studies which involve administration of the phenolic fraction from olive water in rats exposed to oxidative stress from secondary smoke, show a dramatic reduction of stress and protective activity by polyphenols in the diet.

Skin damage and photo protection

The skin damage produced by over exposure to sunrays and environmental stress is related to the destructive activity of free oxygen related radicals produced by skin cells. Polyphenolic components of olive oil have been compared to traditional antioxidants, such as tocopherols, used be the cosmetic and pharmaceutical industry to prevent skin damage. Results show polyphenols is having the highest activity as radical scavengers ( The Olive Oil Source -www.oliveoilsource.com ).