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Olive Oil & Your Health
The
Following Information has been provided by the International Olive Oil
Council
Consumers have growing access to ever more
comprehensive product information. Often this is supplied in publicity by
the companies producing the product, in which case it is always subjective.
Other times the sources are more objective, such as the media, reports by
consumer organizations, and scientific or technical studies, although this
last type of information takes longer to reach the general public. Consumers
pay more attention to food products because the consequences they have can
be beneficial or harmful to health.
Any information on olive oil would be incomplete if it did not take into
account this important facet, especially when the beneficial effects of
consuming olive oil are backed by lengthy, painstaking scientific research.
The fat and oil sector is very complex. Fats and oils have a common
denominator which is their energy value - 9 calories per gram - but the
metabolism of each one or each group differs greatly from the rest. Olive
oil contains a series of compounds that are very beneficial to most
functions of the human body. Highly-qualified members of the scientific
profession now discuss these on the basis of studies and experiments.
Olive oil's biological and therapeutic value is related in many aspects to
its chemical structure. The first aspect is its triglyceride composition,
made up of fatty acids. Olive oil has a prevalence (54 - 83%) of
monounsaturated fat, oleic acid principally, while animal fats are
fundamentally made up of saturated fatty acids and seed oils of
polyunsaturated (50 - 72% in soybean and sunflower oil). Monounsaturated
fatty acids are much more stable than polyunsaturated ones vis-à-vis the
oxidative processes that, if produced, lead to rancidity. Olive oil also has
a low percentage of polyunsaturated fats varying between 3.5 and 22.5%.
These are essential fatty acids that cannot be synthesized by the body.
However, a normal diet covers the essential fatty acid requirements of both
adults and infants and has the best linoleic acid to linolenic acid ratio.
Both olive oil and olive-pomace oil have an identical glyceridic structure,
which means they share the same beneficial properties.
Secondly, olive oil's beneficial properties lie in its minor components. The
most salient ones are the tocopherols, among them alpha-tocopherol which
acts as vitamin E and carotene as provitamin A, and the polyphenols. All of
these components have a major antioxidant function and are closely connected
with virgin olive oils because refining processes alter and partially remove
them in the other types.
Olive oil and the digestive system
According to Char bonnier, olive oil is the oil that is best tolerated
by the stomach due to its high oleic acid content.
The tone of the sphincter which separates the stomach and esophagus and
which impedes the reflux of gastric juices is less affected by olive oil.
Butter is the least tolerated fat, while sunflower oil has intermediate
effects. Gastric emptying time is affected in the same way by these three
types of fat.
Since ancient times olive oil has been described as having a beneficial
effect on hyperchlorohydric gastritis and gastroduodenaal ulcers, which is
attributed to its protective function. When animal fats were replaced by
olive oil in the diets of patients suffering from ulcers the result was a
reduction of lesions in 33% of the cases and cicatrlzatlon in 55% (Taits).
However, prescribing olive oil does not eliminate the need for drugs
therapy.
Two tablespoons of olive oil taken in the morning on an empty stomach appear
to have a positive effect on chronic constipation.
Olive oil has a very positive effect on atony of the gallbladder in that It
has a more acute, gentle and prolonged action than prescribed drugs and
other foods that have similar effects It inhibits hepatobiliary secretion
during gallbladder emptying time and is therefore a pure cholagogue and can
be used as a medicinal food. This effect has been known since ancient times
and has been confirmed recently in numerous studies.
Cholelithiasis (gallstones) is a wide spread illness. It is related to the
metabolism of fats and is found to a greater extent in more economically
developed countries. Overall excess dietary intake, particularly of
saturated fats and cholesterol, leads to increased biliary excretion of
cholesterol and a reduction in bile acids and lecithin. It appears that high
plasma cholesterol levels increase the risk of lithiasis because they
simultaneously raise the fraction of cholesterol transported by the
low-density lipoproteins (LDL) that inhibit the hepatic synthesis of
cholesterol. It is also true, however, that the cholesterol transported by
the high-density lipoproteins (HDL) is more easily metabolized into bile
acids than it is excreted with bile, When a patient with a high cholesterol
level undergoes treatment, plasma cholesterol has to be lowered by
increasing its elimination via the biliary tract. For that reason, the
majority of experts agree that foods rich in saturated and polyunsaturated
fats play a possible role in the formation of calculi, while
monounsaturated-rich olive oil would not appear to play such a role. Olive
oil can be said to have a protective effect against the formation of
gallstones, due to the way in which it activates bile flow and increases HDL,
as well as to its balanced saturates: polyunsaturated ratio and its high
content of monounsaturated. Messini and Cairella have demonstrated that
there is a lower incidence of biliary calculi in areas of Italy where olive
oil consumption is higher.
Olive oil in infancy
Fat intake is important to both the new-born baby and the weaned infant;
even more important is the appropriate intake of essential fatty acids.
Breast-fed babies receive 4 - 5% of their calories in the form of
polyunsaturated acids, while babies fed on cow's milk receive substantially
less. Low linoleic acid intake can delay growth and produce skin, hepatic
and metabolic disorders. Seed oils, which are rich in polyunsaturates, are
not recommended in large quantities for children because it is not advisable
to lower their cholesterol level and because these oils promote peroxidative
phenomena, especially in youngsters with low vitamin E reserves. Hence, it
is important to strike a balance between the dietary supply of linoleic and
linolenic acids because too much of the former can cause disorders of the
nervous system. In his comparison of the effects of olive oil, sunflower oil
and saturated fats on growing rats, Galli detected modifications in the
structural lipids of the brain and liver among the groups treated with
saturated fats and sunflower oil. There were none, however, in the group
treated with olive oil. Olive oil provides a relatively low amount of
essential fatty acids but has a balanced linoleic:linolenic ratio similar to
that found in breast milk.
As regards the influence of olive oil on bone mineralization and
development, a study by Laval-Jeantet demonstrates the need for fats. The
most positive effects are obtained with the intake of oleic glycerides to
which a minimum amount of polyunsaturates is added, and so the best diets
for this purpose are those containing olive oil.
Olive oil and old age
From the very outset, food provides human beings with the energy
necessary for the renewal and continuation of life. Each cell inherits a
program that dictates its biological activity and that can be repeated an
unlimited number of times. Successive repetition, however, produces errors
that are corrected at first, but which over time become consolidated and
give rise to incorrect information to which other errors are added. A diet
rich in polyunsaturated fatty acids can lead to peroxidative phenomena,
which expose cells to this production of errors. On the other hand, the
presence of antioxidant substances, such as vitamin E, provides a defense
mechanism. Mice fed on olive oil have a longer life expectancy than those
fed on sunflower and corn oil. This is explained by the better ratio between
vitamin E and polyunsaturated fatty acids in olive oil. When applied to man,
this research makes for caution in the indiscriminate use of
polyunsaturated-rich oils and leads to a preference for olive oil over other
dietary fats because of its balanced content of linoleic acid, linolenic
acid and anti-oxidant substances.
In a study on skin changes over time, Pinkey reported that people on a diet
consisting of more than 10% polyunsaturates showed signs of aging. 60% of
the cases had skin lesions removed that were suspected of being malignant.
Bone calcification is another problem common in the elderly. Olive oil seems
to have a positive effect, which appears to be dose-dependent, because the
more olive oil ingested the better the bone mineralization obtained. The
explanation might lie in the large amount of oleates in the structural
lipids of bones. According to French researchers, olive oil would appear to
be necessary during growth and later in adulthood to avoid calcium loss.
Old age brings with it reduced digestive capacity and poor absorption of
nutrients, especially of vitamins and mineral salts. Olive oil has the best
characteristics as regards digestibility and absorption and has a mild
laxative effect. Whether consumed cooked, fried, or better yet raw, in order
to make the most of its vitamin and anti-oxidant content, olive oil helps
make food more appetizing and aids digestion.
Olive oil and Arteriosclerosis and Cholesterol
Arteriosclerosis is one of the most widespread diseases in
industrialized countries in which it is the leading cause of death. Together
with genetic predisposition, there are other risk factors that cause the
lesion to appear or become aggravated: smoking, arterial hypertension and
hypercholesterolemia. Additional contributing factors are age, sex (male),
diabetes, gout, a high triglyceride level, oral contraceptives and physical
inactivity.
Cholesterol belongs to the sterol group and is a lipid that is abundant in
animal tissue, insoluble in water and soluble in organic solvents. It forms
part of cell membranes and in many cases constitutes a stable complex with
phospholipids. In the body, cholesterol serves as the basis for the
synthesis of other steroids involved in important processes such as the
formation of bile acids that emulsify dietary fats so that they can be
absorbed by the intestinal epithelium, or in the regulation of vitamin D.
The incidence of arteriosclerosis is closely linked to dietary habits. A
diet rich in animal fats tends to raise plas-ma cholesterol. On the other
hand, vegetable oils rich in polyunsaturated acids have an anti-atherogenic,
protective action against cholesterol, and lower cholesterol levels.
As previously mentioned not all plasma cholesterol is atherogenic. The
cholesterol transported by the low-density lipoproteins (LDL-cholesterol) is
particularly so, whereas the cholesterol carried by the high-density
lipoproteins (HDL-cholesterol) appears to have a protective effect since
their function is to eliminate free cholesterol in the cells and to esterify
and carry it to the liver where it is emptied with the bile.
Numerous studies have confirmed a negative correlation between plasma HDL
levels and arteriosclerosis and a positive correlation between HDL and a
longer life expectancy.
Any treatment of hypercholesterolemia must begin by lowering saturated fat
intake. The suppression of these fats produces a reduction in plasma
cholesterol double that obtained through the addition of an equal amount of
polyunsaturated-rich lipids (Keys, Grande Covian et al.). If the
substitution is with olive oil, which is rich in monounsaturates, the total
cholesterol level is approximately equal to that obtained through the
reduction of saturated fat intake. The positive effect of monounsaturated
fats is not limited to a similar substitution effect as for polyunsaturated
fats. It also increases HDL cholesterol and helps protect against coronary
mortality. A comparative study of deaths from coronary disease in 10,000 men
has indicated that at the same plasma cholesterol levels, the risk of
developing this type of disease was approximately the same in American and
Finnish men, while it was much lower in Mediterranean men who consumed a
high percentage of olive oil among other fats.
When eaten in excess, polyunsaturate-rich vegetable oils peroxidize easily
and for that reason can become atherogenic. This is a possible cause of
endothelial lesions and platelet hyperaggregation.
A fitting conclusion to this chapter is to point out that the most important
step in the prevention of arteriosclerosis is to lower animal fats - visible
and invisible - and to replace them by monounsaturated-rich olive oil, which
also contains a balanced amount of polyunsaturated adequately protected by
anti-oxidants like alpha-tocopherol or polyphenols. This dietary approach,
which has been confirmed by experimental and epidemiological research, will
permit rational disease prevention and satisfactory control of plasma
cholesterol, without the risk of undesirable side effects.
Olive oil and frying
To make food more appetizing, man uses cooking methods like boiling, baking,
smoking and frying, with the highest temperatures being reached during
frying.
The temperature inside fried food remains almost constant at 100 degrees C
until its water content evaporates. At that point the hot oil can penetrate.
The food cooks quickly and the loss of nutritional value is lesser than with
other cooking methods, according to studies by Varela. A crust forms
on the outside as a result of the reaction with the hot oil, which
coagulates proteins and caramelizes the glycides. Less fat is consumed than
with other cooking methods, as the oil is not absorbed by the food.
Fats are subjected to auto-oxidative phenomena that are accelerated as
temperatures rise. These phenomena are heightened by the degree of
un-saturation of the fat and the presence of pro-oxidant substances, while
they are checked by antioxidants. Some of the products of deterioration
formed are volatile and easily eliminated; others (polymers) are poorly
absorbed and some of those that remain can be toxic and can affect different
organs and detract from the nutritive value of the food.
Animal fats, which have a low degree of un-saturation, do not contain
antioxidants and soon undergo auto-oxidation. Seed oils are highly
unsaturated and oxidize rapidly. On the contrary, olive oil is very stable
because of its intermediate degree of un-saturation and the anti-oxidants if
contains. Besides being affected by the type of fat, deterioration is
related to the temperature reached, heating time, type of food involved, and
the presence of catalysts.
Fedeli has demonstrated the stability of olive oil at high frying
temperatures, and Varela has proven that food digestibility is not
modified by frying in olive oil, not even when the same oil was used 10
times over to fry meat and sardines. This research would appear to indicate
that olive oil is the oil best suited to frying owing to its higher
resistance to oxidative deterioration.
To sum up this entire chapter, we can conclude that owing to its fatty acid
structure, Its content in vitamin E and other anti-oxidants, its balanced
contents of other components, and its aroma and flavor, olive oil is the oil
that is best suited to human consumption -whether raw or cooked - and has a
protective effect on human health.
O'Casha Olive Oil, Health, Olive Oil, Bulk, Drum, Wholesale, Olive Oil
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