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Cardiovascular diseases are the
top cause of death in the industrialised world. A host of studies have
documented that arteriosclerosis is closely linked to eating habits, lifestyle
and some aspects of economic development. The progression of arteriosclerosis
depends on many factors: the most important ones are high blood cholesterol,
high blood pressure, diabetes and cigarette smoking.
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What is
arteriosclerosis?
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Arteriosclerosis is the
condition in which cholesterol-rich patches (known as atheromas) deposit on the
walls of the arteries. This stops blood from reaching the tissues and obstructs
the functioning of vital organs, such as the heart and brain.
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What are its
consequences? |
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When the heart is affected,
arteriosclerosis causes angina and heart attack and it increases the risk of
sudden cardiac death. When the brain is attacked, cerebral thrombosis occurs,
leading to muscular paralysis, loss of cognitive capacity and the risk of
dementia. The aorta and leg arteries may also be damaged, causing pain and
difficulty in walking and the risk of necrosis and gangrene.
When a fatty
patch bursts, for instance because of a rise in blood pressure, the small
arteries in the patch also burst. This triggers a response where certain cells
found in blood, known as platelets or thrombocytes, join together to form a
thrombus or blood clot.
The blood clot travels through the arteries, but
when it is larger than the vessel it causes blockage. Because blood cannot get
through, the tissue or organ dies.
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Olive oil and
arteriosclerosis |
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It has been demonstrated
that olive oil has an effect in preventing the formation of blood clots and
platelet aggregation. It has been observed that by avoiding excessive blood
coagulation, olive-oil-rich diets can attenuate the effect of fatty foods in
encouraging blood clot formation, thus contributing to the low incidence of
heart failure in countries where olive oil is the principal fat
consumed.
Cholesterol is a fatty
substance contained in foods of animal origin. Diets containing a large amount
of animal fats raise blood cholesterol level, which is one of the chief 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 atherogenic, 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
(known as HDL-cholesterol) is called "good cholesterol" because it provides
protection against the onset of cardiovascular diseases. The high-density
lipoproteins remove free cholesterol from the cells, then esterifying it and
transporting it to the liver where it is eliminated with bile.
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Olive oil and
cholesterol |
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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 role and prevents the formation of fatty patches, thus
stimulating the elimination of the low-density lipoproteins.
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 incidence of depression in the modern-day world
and the great risk it poses in recurrent heart disease.
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