Cholesterol, a yellow fatty substance, is useful for many metabolic functions. But a high blood level (hypercholesterolemia) is harmful for health.

Cholesterol helps in building outer membrane of body cells. It is the principal ingredient in the digestive juice bile  that helps to digest fats. It is present in the sheaths that insulate nerves.

Sex hormones contain cholesterol. It performs several functions such as transportation of fat in the body, providing defense mechanism, protecting red blood cells and muscular membrane of the body.

Most of the cholesterol found in the body is produced in the liver. However, about 20 to 30 per cent generally comes from the foods we eat. Extra cholesterol is excreted through bowels and kidneys. Normal level of cholesterol varies between 150- 250mg per 100ml.    Levels above 250mg/100ml    accelerate the deposition of fat in the blood vessels, thus blocking the lumen and impairing blood flow. This increases   risk of hypertension, heart diseases and stroke.

Genetic susceptibility exists for hypercholesterolemia. Diabetes also increases cholesterol levels in the blood. Kidney and liver diseases are also known to lead to high cholesterol levels. Impaired functioning of the thyroid gland also augments the cholesterol levels in the body. Prolonged starving as in anorexia nervosa causes cholesterol levels to rise. Some of the drugs used to treat HIV cause hypercholesterolemia as secondary effect. 

A high fat diet, lack of physical activity and obesity directly  contribute to high cholesterol levels in the body and its attendant complications. Mental and physical stress leads to increased production of adrenaline and cortisol in the body, which mobilises fats causing high cholesterol levels.

When the body’s cholesterol levels become high, it tends to be deposited on skin and tendons. White or red patches are formed around the eyes. Hypertension is the direct result of increased cholesterol levels in the blood. As the blood vessels supplying blood to limbs, get thickened due to high cholesterol levels, there is reduced blood circulation causing muscle cramps. These cramps occur on working or walking and reduce while one is resting. Affection of the coronary vessels, which supply blood to heart, is responsible for causing heart attacks. Similarly, strokes are the result of blood vessels of the brain being affected by high cholesterol levels.

Diagnosis of cholesterol level is done by a simple blood test.

Considering the health hazards of high cholesterol levels, it is important to prevent this condition by taking a low fat diet. Foods containing saturated fats like cheese, butter, margarine, cream, ghee, animal fats, among others, should be avoided. All meat products except fish are high in cholesterol. Eggs also have a high cholesterol content. Processed and tinned foods also tend to raise blood cholesterol levels.

Whole grains, vegetables, fruits, fish and plant products are low in cholesterol and should be the diet of choice if one wants to keep good health. Adequate physical exercise is must to maintain the ideal body weight and cholesterol.

If in spite of the preventive measures, one does have high blood cholesterol levels, it can be brought down by lipid lowering drugs.

Dr Rachna Pande is an specialist in internal medicine at Ruhengeri Hospital

rachna212002@yahoo.co.uk