What is Cholesterol?
Cholesterol is a wax-like substance with a quite complex chemical formula. It belongs to the class of sterol (steroid and alcohol) lipids. It is produced in the liver, or rather the bile, at a rate of approximately 1gr. per day. Bile is stored in the gallbladder and is needed to digest fat. Cholesterol is not soluble in water but is soluble in blood. It’s transported in the blood by way of lipoproteins.
The most important function of cholesterol is the building up of cell membranes. Without a membrane there would be no cells and hence no life. Cholesterol is responsible for the flow of membranes, their permeability and maintenance. It’s also connected to the production of hormones such as cortisol, estrogen and testosterone.
Why then can cholesterol be bad? The difference lies in the lipoproteins which transport cholesterol in the blood to the cells where it is needed. Basically, there are two types: low density lipoprotein (LDL) and high density lipoprotein (HDL). Low density lipoprotein is the bad cholesterol carrier. If too much circulates in the blood, it can build up thick layers in the walls of the arteries, which is a major cause for heart attack and stroke, because it clogs the arteries and prevents the free flow of blood.
On the other hand, high density lipoprotein transports cholesterol which is not needed back to the liver, where it is processed and secreted. That’s why HDL is referred to as the good cholesterol.
Scientific studies and results vary concerning good and bad cholesterol as causes for heart attack and cardiovascular illness. They also vary on the level of cholesterol which can be considered dangerous, but it’s thought that 100mg or less of LDL and a total of no more than 200gr is desirable.
Where are the Dangers?
Obviously, the dangers lie in the existence of a high level of LDL in the blood which can clog up the arteries and lead to heart disease. It is said, that the body produces enough cholesterol in the liver, to cover the daily requirement and that there is no need to add cholesterol by way of food. The dangers therefore lie in the wrong diet. Cholesterol is found in all sorts of animal products, particularly animal fat such as butter and lard. But animal meat also contains cholesterol, even poultry and fish. Cholesterol is absent in plants.
A strictly vegetarian diet would keep cholesterol levels under control, but it can lead to other deficiencies if not supplemented properly. It’s also not to everybody’s taste. There is nothing wrong with a mixed diet, as long as the cholesterol levels are regularly tested and the intake of animal fat kept to a minimum. Cholesterol testing for the average adult is recommended every five years, but it should be done more frequently in older people and those already suffering from obesity or high cholesterol levels.
What to Do?
As mentioned above, testing of the cholesterol levels and a balanced diet, including plenty of fruit and vegetables, provides good protection. Artichokes are particularly helpful. In addition, exercise increases HDL levels in some people, but as physical inactivity is generally a cause for heart disease, some kind of sports and exercise are recommendable.
A good source of further information regarding cholesterol, alcohol and smoking as well as heart disease is the following link: www.americanheart.org.