Serum cholesterol is the total amount of cholesterol found in your blood. It is a soft, waxy substance found in the blood and cells of the body. Contrary to popular belief cholesterol is not all bad. It is in fact an integral part of cell membranes, used as to make hormones and is a vital ingredient in many other physiological processes. There are several types of cholesterol found in the blood. The measurement of serum cholesterol encompasses all these different types. Some types are more beneficial than others.
Types of Cholesterol
A lipoprotein is a carrier molecule made up of proteins and lipids. The core of the lipoprotein contains lipids and the outer surface is made up of phospholipids, apoproteins and cholesterol. This is how cholesterol is transported in the blood. Different carrier molecules differ in the ratio of lipid and apoprotein which they contain. The two main types of cholesterol include:
LDL (low density lipoprotein) Cholesterol: LDL cholesterol has been dubbed "bad cholesterol." LDL cholesterol primarily transports cholesterol and other lipids from the liver to other cells in the body via the bloodstream. Unfortunately as LDL cholesterol travels through the blood, it can get deposited into artery walls. In an attempt to clean up the lodged cholesterol, white blood cells flock to the area. Gradually, a bump known as a plaque builds up in the area, containing the lodged cholesterol, dead cells and debris. Such plaques cause a hardening of the arteries, also known as atherosclerosis. Furthermore, should the surface of the plaque rupture, blood clots can form, increasing the risk of a heart attack. The cells beyond the blockage are blocked from the blood flow and die as they don’t receive nutrients. It is then more desirable to have lower levels of LDL cholesterol
HDL (high density lipoprotein) Cholesterol: HDL cholesterol is also known as "good cholesterol." This is because HDL is said to carry cholesterol away from cell and arteries, back to the liver where it can be disposed of. Note that this is in the opposite direction as LDL cholesterol. This would decrease the rate of formation of plaques and the resulting consequences. Therefore, higher levels of HDL cholesterol are more desirable.
How are serum cholesterol levels measured?
A cholesterol test is also known as a lipid panel or lipid profile. You would normally be asked to fast for about 9–12 hours, but are allowed to drink water during that time. A blood sample is then taken and tested in a laboratory.
What do your serum cholesterol results mean?
Below 200 md/dl – This is the optimal serum cholesterol reading and you have a low risk of coronary heart disease.
200 – 239 mg/dl – This is considered a borderline to high risk level. In this case, your doctor will analyze your results to see if the levels of LDL cholesterol and the balance of HDL cholesterol. Some lifestyle changes or medication may be suggested by your doctor.
240 mg/dl and above – Individuals is serum cholesterol levels this high have twice the risk of coronary heart disease compared to those with a reading of below 200 md/dl. Further analysis and potential treatments will be discussed by your doctor.