Cholesterol, a yellowish fatty substance, is one of the essential ingredients of the body. It forms the building block of the outer membrane of cells and is the principal ingredient of the digestive juice needed to metabolise fat. It is also present in the fatty sheaths that insulate nerves and in sex hormones. Cholesterol performs several functions in the body.

Normal level of cholesterol varies between 150 and 250 mg. per 100 ml. And although useful to the body, excess cholesterol is harmful. In blood, cholesterol is bound to lipoproteins. There are two main types of lipoproteins: a low density one (LDL) and a high density one (HDL). The low density lipoprotein is the one which is harmful and increases risk of heart diseases, while high density lipoproteins (HDL) are useful. Meanwhile, higher levels of HDL minimise the risk of heart problems.

Excess cholesterol in the body accelerates the deposition of fat over the inner lining of blood vessels. This occludes their lumen, thus impeding free flow of blood and necessary oxygen (carried by blood) to various body parts. Total obliteration of the coronary (bringing blood to heart) vessels can lead to heart attacks, while blockade of blood flow to brain can result in stroke. A small clot can break from the fat deposit over the blood vessels and pass to the brain or lung causing serious problems. Impaired blood supply to the limbs can lead to painful cramps while working or walking. Occlusion of the vessels can cause high blood pressure.

 Mostly saturated fats in the diet, lead to elevated cholesterol levels. Intake of fried foods, cheese, margarine, cream and butter, eggs, meat products except fish, all increase the risk of high cholesterol levels in the body.

Lack of exercise also leads to obesity and high cholesterol levels in the body. Alcohol and cigarette smoking further contribute to the process.  Physical and mental stress release hormones which tend to increase the blood cholesterol levels. Apart from these, in some people high cholesterol levels are inherited via genes.

Some middle aged persons, mainly women have orange, yellow pigmentation around eyes, suggestive of high blood cholesterol. In elderly people it may manifest as a whitish ring around the eye ball. But apart from this, there are no external features suggestive of high blood cholesterol.

 High cholesterol levels are diagnosed by a simple blood test. It is ideally done   without food in the morning so that food taken does not influence the results.  Lipid profile asked by a doctor includes the total cholesterol, high and low density lipoproteins and total triglycerides (another component of fats in the blood).

To prevent high cholesterol levels and its attendant problems, one should avoid taking foods with high amount of fats. Intake of plenty of fresh vegetables and fruits, whole grains, nuts and fish helps in keeping blood cholesterol levels within normal limits.  One should try to quit alcohol and smoking.

Regular physical exercise is very useful to burn the extra calories consumed and helps to keep blood cholesterol within normal range.

One should get tested for blood cholesterol after 40 years or so of age, at least once in a year. By this age, process of deposition of fat over blood vessels progresses enough to cause heart problems.

If the blood cholesterol is high in spite of preventive measures, there is a need to take cholesterol lowering drugs. These drugs are taken under medical supervision and can be stopped after the levels come normal.

As more people become aware of the harmful effects of high blood cholesterol, many related problems can be prevented or minimized.

Dr. Rachna Pande is a specialist in internal medicine at Ruhengeri Hospital

E-mail-rachna212002@yahoo.co.uk