Cholesterol isn’t just something that sits in your body like fat around your waist. It’s carried through your bloodstream by carriers made of fat (lipid) and proteins. These are called – no big surprise – lipoproteins.
Two types of lipoproteins carry cholesterol to and from cells. One is low-density lipoprotein, or LDL. The other is high-density lipoprotein, or HDL. The amount of each type of cholesterol in your blood can be measured by a blood test.
LDL cholesterol is called “bad” cholesterol. Think of it as less desirable or even lousy cholesterol, because it contributes to fatty buildups in arteries (atherosclerosis). Plaque buildups narrow arteries and raise the risk for heart attack, stroke and peripheral artery disease can narrowed arteries in the legs).
HDL (Good) Cholesterol
HDL cholesterol is “good” cholesterol. Think of it as the “healthy” cholesterol, so higher levels are better. Experts believe HDL acts as a scavenger, carrying LDL cholesterol away from the arteries and back to the liver. There it’s broken down and passed from the body.
A healthy HDL cholesterol level may protect against heart attack and stroke. Studies show low levels of HDL cholesterol increase the risk of heart disease. HDL cholesterol does not completely eliminate LDL cholesterol. Only one-fourth to one-third of blood cholesterol is carried by HDL.
Triglycerides are the most common type of fat in the body; they store excess energy from your diet. A high triglyceride level combined with low HDL cholesterol or high LDL cholesterol is linked with fatty buildups in artery walls. This increases the risk of heart attack and stroke.
This content was last reviewed April 2017.