Almost all of us know somebody with high cholesterol, if not ourselves. Detecting it is simple. A test will give you reliable data on the amount of cholesterol in your blood. Controlling this level is not all that complicated either, since diet has a direct effect on whether it rises or falls.

But how does cholesterol affect our health?
First of all, cholesterol is essential for the body to function properly. So zero cholesterol is not compatible with life. It is a fat that is found in blood and which takes part in synthesis of hormones such as the sexual ones, formation of cell membranes and in digesting food. Some of the cholesterol in the body is formed by the body itself, while other cholesterol comes in with the food we eat.�

Both are transported by two types of lipoproteins, low-density ones or LDL, known as bad cholesterol, and high-density ones, HDL or good cholesterol. While the former accumulates in the arteries, possibly blocking them and giving rise to cardiovascular problems, the latter frees arteries of such obstructions. When cholesterol levels go above 200 mg/dl, and the LDL level is more than 135 mg/dl, this is known as hypercholesterolemia.

The main sources of high cholesterol are animal-based or saturated fats. This group includes sausages, whole milk, store-bought pastries, fatty meats like lamb, pat�, bacon and two kinds of fat, which raise cholesterol levels even though are vegetable-based: coconut and palm oil. It is a good idea to limit, but not eliminate altogether, your intake of beef and ox meat, sunflower oil, shellfish and vegetable margarine. Several years ago it was believed that eggs were the one of the black sheep of hypercholesterolemia, but today we know that their influence is not so critical. Eating eggs as part of a balanced diet does not affect your cholesterol level.�

As for healthy foods, we can mention practically all fruits and vegetables, lean meats such as skinned turkey and chicken, all nuts except peanuts, juice, honey, home-made pastries and of course olive oil and blue-meat fish. It is also a good idea to eat whole-grain pasta, bread and cookies. The good thing about these foods is that they do not raise levels of bad cholesterol and can even make them go down, as is the case of blue-meat fish, which are rich in Omega 3 fatty acids, and nuts, especially walnuts which help expel bad cholesterol through the liver. A study by the Hospital Cl�nico in Barcelona suggests that consuming 10 walnuts a day for 6 weeks reduces cholesterol levels by 11 mg/dl.

Also well known are the effects of extra-virgin olive oil (this kind of olive oil retains all its properties) in fighting bad cholesterol and how it helps the good cholesterol. Vegetables like tomatoes, rich in lycopene, prevent LDL from oxidising and forming atheroma platelets that build up in blood vessels.

Fiber offers special advantages. A study published in the American Journal of Clinical Nutrition compared the effects on cholesterol of a low-fat diet, and then this kind of diet augmented by intake of fiber. The results showed that people who ate fiber reduced their total cholesterol by another 4% and reduced the bad cholesterol by as much as 7% while levels of good cholesterol rose as well. This happens because soluble fiber attracts and drags away bile acids from the liver, impeding their reabsorption. As the body needs these acids, and their synthesis involves cholesterol, more cholesterol is drawn away from the blood to make up for the acids that have been eliminated. Fiber also acts in the intestine, reducing its assimilation of fats.�