HDL Cholesterol vs. LDL Cholesterol

All cholesterol isn't the same. There's HDL cholesterol ("good") and LDL cholesterol ("bad"). Both types of cholesterol molecules travel through the bloodstream in globular packages in combination with lipoproteins, and they perform different functions.

What is HDL?

High-density lipoproteins (HDL) are small, dense molecules responsible for transporting cholesterol to the liver.

HDL is good for your body because it helps remove cholesterol from the arteries and protects against dangerous blockages (plaques) in the arteries. HDL cholesterol is also less likely than other forms of cholesterol to oxidize and leave sticky plaques on artery walls.

"Your good HDL cholesterol hustles your bad LDL cholesterol to your liver to disposal before it can plant itself like barnacles in your arteries," say doctors Mehmet C. Oz, M.D., and Michael F. Roizen, M.D.

People who exercise, don't smoke, and maintain a healthy weight tend to have higher levels of this “good” cholesterol. Low HDL levels can be a risk factor for coronary heart disease (CHD), while high levels (>60 mg/dL) help reduce CHD risk.

Here's why exercise is a powerful way to improve your cholesterol.

What is LDL?

Low-density lipoprotein (LDL) carries the majority of cholesterol through your bloodstream and delivers it to the cells of the body. These molecules are larger, less dense, and less stable than HDL. They readily oxidize and deposit plaques on arterial walls to likely to clog arteries and lead to cardiovascular disease. That's why LDL is known as the "bad" cholesterol.

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