High Blood Cholesterol

It is generally known that the risk of heart disease rises as a person’s blood cholesterol levels increase. It is, however, important to distinguish in this context the different types of cholesterol found in the human body.

Cholesterol is a soft, fat-like substance used to form certain tissues in the body, especially nerves. Your body derives the cholesterol which it needs from your daily diet. The fat in the food which you consume is digested in the body and taken to the liver, where it is processed into cholesterol.
The two main types of cholesterol are low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol. LDL cholesterol is commonly referred to as “bad” cholesterol because it carries fat from your liver to other parts of the body. The higher the level of LDL in your blood, the greater the likelihood that cholesterol will deposit within the walls of your blood vessels. This in turn increases your risk of developing atherosclerosis.
Conversely, HDL cholesterol is called “good” cholesterol because it is believed to help your body get rid of cholesterol by transporting fat and LDL cholesterol deposits to the liver for breakdown, thereby “cleansing” the arteries.
Thus, to protect yourself against cardiovascular disease, you would want your HDL (good) cholesterol level to be high and your LDL (bad) cholesterol level to be low. An excessive amount of LDL in the blood is a cardiovascular risk factor; likewise if your HDL level is abnormally low.
As a general guide, the average adult should maintain his LDL cholesterol level at less than 3.4 mmol/L (130 mg/dl), his HDL cholesterol level at 1.0 mmol/L (40 mg/dl) or above, and his total cholesterol level at less than 5.2 mmol/L (200 mg/dl). If he has other risk factors for cardiovascular disease, he should aim to keep his LDL and total cholesterol levels even lower at below 2.5 mmol/L (100 mg/dl) and below 4.1 mmol/L (160 mg/dl) respectively. These parameters are summarised in the table below.

Desirable Cholesterol Levels

Cholesterol in mmol/L (mg/dl)

Average Adult (without known coronary risk factors)

Adult with heart disease / diabetes / other coronary risk factors

LDL Cholesterol

< 3.4 (130)

< 2.6 (100)

HDL Cholesterol

≥ 1.0 (40)

≥ 1.0 (40)

Total Cholesterol

< 5.2 (200)

< 4.1 (160)


Healthy cholesterol levels can be attained by combining a low-fat diet with exercise and weight control.