Healthy blood cholesterol levels help promote heart health. Blood tests often measure total cholesterol as well as LDL and HDL cholesterol.

LDL (low density lipoproteins) transport cholesterol to the tissues throughout the body. LDL is often called "less healthy or bad" cholesterol.

HDL (high density lipoproteins) collect cholesterol from the tissues and transport it back to the liver for recycling or disposal. HDL is often called "healthy or good" cholesterol.

A variety of factors affect LDL and HDL cholesterol levels. Low levels of LDL relative to HDL help to protect against heart disease