Olive oil and Health

When cholesterol does not exceed certain limits, it is vital to the structure of the cell walls in our bodies. However, cholesterol which is synthesized in the liver cannot move by itself in our bodies. Lipoproteins play this role of circulating the cholesterol. The two main types of these are LDL (low density lipoprotein) and HDL (high density lipoprotein). LDLs are some of the Lipoproteins that transfer cholesterol to the cells. But the paths for cells are often too narrow for these LDLs, so they get stuck and with time they completely block the arteries. The more HDL we have, the easier it is to open the paths and rid the body of unwanted cholesterol. The body needs a good ratio of HDL to LDL.

Eating olive oil increases the composition and concentration of HDL cholesterol (good cholesterol) and at the same time makes LDL cholesterol (bad cholesterol) less able to block arteries by both preventing its oxidation and metabolizing the size of its molecules. Olive oil is one of the most important factors, especially for arteriosclerosis of peripheral arteries. In conclusion, olive oil controls the level of LDLs, while increasing HDL levels, and thereby reduces the incidence of heart attacks. The protection monounsaturated fatty acids give against the risk of cardiovascular diseases was confirmed by the American Food and Drinking Organization (http://www.fda.gov/-dms/qhchoice/html ) for the first time in 2004.

Virgin olive oil is the most easily digested edible fat, helps in assimilating vitamins A, D and K, absorbing nutrients, especially vitamins and minerals, and also protects against gastritis and ulcers. It is a cholagogue, meaning that it activates secretion of pancreatic and bile hormones. This reduces the chance of cholelithiasis (formation of stone in the bile). Olive oil is not only easy to digest, but it also helps in digesting other fats because it helps the excretions of the digestive system and stimulates the pancreatic lipase enzyme.

Olive oil reconstitutes the shape and function of the liver cells, replacing other lipids in them. Also, in the intestine, olive oil increases calcium absorption and can therefore reduce osteoporosis. Two tablespoons of olive oil, when taken in the morning on an empty stomach, seem to have a positive effect on chronic constipation, so ancient Greeks were in the habit of eating 1-2 tablespoons of olive oil each morning.

Diabetes mellitus is widespread throughout the world. Those with the disease cannot produce or use insulin, meaning that carbohydrates, lipids and proteins are not metabolised properly.

Sirtori (1986) argues that when olive oil is taken as the sole source of fat, especially by people with diabetes, it works favorably in the slow evacuation of stomach contents in the duodenum.

Oxidation is a process that takes place not only during the production of oil but also in our own bodies. Reactions which activate the formation of free radicals (peroxides) are continually taking place in our bodies. As a rule, free radicals do not cause significant damage, thanks to the protection provided by antioxidants which help maintain balance up to a point. If this equilibrium is disturbed, however, this leads to “oxidative stress”, which in turn leads to the deterioration of normal cellular functions, and even to the death of cells.

Oxidation is a complex, fundamental phenomenon which is part of the process of cell aging. Lipid or fat peroxidation tends to be in proportion to the number of double bonds in a compound, which explains why oleic acid appears to have low oxidation susceptibility.

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, they do not deteriorate as much and ageing is slower.

About 1.5% of olive oil is unsaponifiable, and contains antioxidants. Virgin olive oil contains the largest quantities of these substances, as well as other secondary elements

The antioxidants in olive oil

Vitamin E (alpha-tocopherol), carotenoids and phenolic compounds (simple phenols, such as hydroxytyrosol and complex phenols such as oleuropein) are all antioxidants whose activity has been proven in vitro, but also more recently in clinical trials which revealed additional roles in the prevention of certain diseases and the delaying of aging.

The phenolic content of olive oils 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 instance hydroxytyrosol inhibits platelet aggregation and it is anti-inflammatory and oleuropein encourages the formation of nitric acid, which is a powerful vasodilator and exerts a strong anti-bacterial effect.

Oxidized LDL-cholesterol is known to be potentially damaging to arteries. This is where olive oil comes into its own as it has a beneficial, protective effect against the oxidation of LDL-cholesterol. In addition, it strengthens other cells of the body against the toxic effects of oxidants.

The high content of antioxidants in the Mediterranean diet seems to contribute significantly to the longevity of Mediterranean peoples.

Antioxidants are found in fresh fruits and vegetables. As it is the only oil produced from fruit, olive oil retains many ingredients, antioxidants and vitamins, which give it extra nutritional value. The explanation behind this high antioxidant content probably lies in the fact that, because the olive is a fruit and is exposed to air, it must be protected from oxygen. Therefore, it synthesizes a large number of antioxidants, which are also found in olive oil.

Virgin olive oil, i.e. oil that is made without chemicals or industrial processing, is particularly rich in these substances and has a strong antioxidant effect, providing protection against damage caused by free radicals (cleansing action) as well as against the onset of cancer. www.internationaloliveoil.org

Epidemiological studies have shown that olive oil has a protective effect against some malignant tumors (chest, prostate, endometrium, digestive tract). Numerous research studies have shown that olive oil reduces the risk of breast cancer. A healthy diet, with olive oil being the main source of fat, significantly reduces the risk of cancer. The reason is that cancer cell mutations are partly due to toxins that, when ingested through diet, attack the DNA. When they pass through the liver, these toxins produce free radicals, which then attack the DNA. In order to fight these free radicals, the body needs vitamins and antioxidants such as those contained in olive oil.

It has also been reported that a diet rich in olive oil is associated with a reduced risk of developing bowel cancer. The protective effects of olive oil are not related to the amount of fruit and vegetables taken through the diet.

Recent research has shown that olive oil provides protection against colorectal cancer. Recently, research has been focusing on the metabolic effects of fats, in particular on the protective role of olive oil in chronic liver disease and on bowel dysfunction, also known as Crohn’s disease. The results are focused on the beneficial effects of olive oil on precancerous lesions. After analyzing three types of diet, the investigating scientists arrived at several conclusions:

-A diet including olive oil reduced the number of cancerous lesions

-The number of tumors that were created was noticeably and significantly low

-The tumors were less aggressive and had a better prognosis

This beneficial effect could be related to oleic acid, the basic monounsaturated fatty acid in olive oil. It has been observed that this fatty acid reduces the production of prostaglandin which is derived from arachidic acid, which in turn plays an important role in the formation and growth of tumors.

However, it is possible that the remaining components of olive oil, such as antioxidants, flavonoids, polyphenols and squalene also have a positive effect. Squalene is considered to have a beneficial effect on the skin, reducing the risk of melanomas.

Olive oil also strengthens the taste of vegetables and legumes, which have also been proven to deter cancer. Some recent and promising research focuses on the protection afforded by olive oil against childhood leukemias and various forms of cancer such as esophageal cancer. www.internationaloliveoil.org

Olive oil plays a key role in the development of the fetus during pregnancy, and any deficiency in olive oil may have detrimental effects on the later development of the infant.

It has been shown that the post-natal growth of babies born to mothers who consume olive oil during pregnancy is better in terms of height, weight, behavior and psychomotor reflexes.

Fetuses need vitamin E to grow. The newborn infant also needs a vitamin E reserve to combat the oxidative stress created when it enters an atmosphere with oxygen. Although vitamin E is not particularly abundant in olive oil, it is present in sufficient quantity thanks to the oil’s resistance to oxidation.

Therefore, both the amount and type of food consumed during pregnancy play a key role in the metabolic adaptations taking place in the mother and in her functional relationship with the fetus.

Olive oil and breastfeeding

During labour, the vitamin E in the mother’s blood is concentrated in the breast glands and so, during breast feeding, the mother continues to supply vitamin E. It is essential to maintain the levels of this vitamin during breast feeding.

Vitamin E is also recommended for premature and newborn infants with renal or pancreatic insufficiency due to its beneficial effect on the hepato-biliary system.

But olive oil does not only provide enough essential fatty acids for the development of the newborn child. The linolenic to linolenic acid ratio (essential fatty acids) is similar to that of breast milk. The beneficial effect of oleic acid lasts beyond pregnancy. In addition to proven efficacy in the prevention of hypercholesterolemia and atherosclerosis, which is a condition that can begin at an early age, oleic acid seems to also have a positive effect on bone growth and mineralization as well as on growth during infancy

Nutritional requirements

During pregnancy and lactation, it is recommended that women consume more fat, especially monounsaturated fat, and also reduce saturated fat and cholesterol intake to the greatest extent possible. General dietary guidelines should be followed and calorie intake should be controlled to avoid excessive weight gain.

Under-three-year-olds have different dietary requirements to children over this age. Forty per cent of the energy they consume comes from fat, whether it be in breast milk or any other kind of milk. It is recommended to maintain this dietary pattern and to ensure that energy and nutritional intake cover the developmental requirements of the child. www.internationaloliveoil.org