Structure & Function of Cholesterol

Cholesterol, which humans produce themselves and consume in their diets, is one of the building blocks of cell membranes and is used to form hormones such as androgen and estrogen. While a certain amount is required for healthy bodily functions, too much cholesterol can cause heart disease and lead to death.

Structure

• Cholesterol is a soft, waxy compound that circulates in the bloodstream. When formed, these compounds attach themselves to two unique types of carrier proteins, HDL (high-density lipoproteins) and LDL (low-density lipoproteins).

Function: LDL

• Cholesterol that is attached to LDL proteins has a negative function within the body. These cholesterol molecules attach themselves to the walls of the blood vessels and arteries, causing them to narrow. Eventually, this narrowing of the arterial pathways can cause a heart attack.

Function: HDL

• Cholesterol that is attached to HDL proteins has a beneficial function within the body. HDL cholesterol molecules are able to attach themselves to harmful LDL molecules and carry them off to the liver where they are broken down and removed from the body.

Expert Insight

• The American Heart Association advises individuals to have total cholesterol (measured in milligrams per deciliter of blood) of 200mg per deciliter or less. The majority of the total cholesterol should be made up of HDL cholesterol.

Identification

• The total cholesterol count and the proportion of HDL to LDL cholesterol is determined using a blood test. The blood is then analyzed using special equipment that determines the amount of cholesterol that is present.