The most important mechanism by which HDL exerts its antiatherogenic role is the removal of excess cholesterol from peripheral cells and its transport to the liver, a process commonly termed the reverse cholesterol transport system (RCT). Several proteins are involved in this process, including ATP-binding cassette transporter 1, LCAT, CETP, and hepatic triglyceride lipase (see Pathophysiology). 
But keep in mind that not all cholesterol is created equally. LDL cholesterol, also known as “bad cholesterol,” is the form that can build up on the artery walls and increase your risk of heart disease. HDL cholesterol, on the other hand, is often dubbed “good cholesterol” because it travels through the bloodstream, removing harmful cholesterol from the arteries to help enhance heart health.
The small HDL particles consist of the lipoprotein ApoA-1, without much cholesterol. Thus, the small HDL particles can be thought of as “empty” lipoproteins, that are on their way to scavenge excess cholesterol from the tissues. In contrast, the large HDL particles contain a lot of cholesterol. These particles have already done their scavenging work, and are just waiting to be taken back up by the liver.
If you don’t already know your HDL level, you can find out from blood work that includes a lipid profile. This profile tells you your overall total cholesterol as well as its individual parts, including HDL and LDL. There are no obvious signs or symptoms of high LDL cholesterol and low HDL cholesterol so it’s very important to maintain a healthy lifestyle and get your cholesterol checked regularly!
There's no magical food to keep your heart healthy, but there are a lot of foods that can help—including these foods that help lower your cholesterol. In addition to cutting back on foods that can raise total cholesterol and getting enough exercise, make sure to eat more of these foods that improve your cholesterol profile by raising "good" HDL and/or lowering "bad" LDL cholesterol. These foods include some old standbys, such as oatmeal and fruit, plus a few surprising foods that can help lower cholesterol to reduce your risk of heart attack and stroke.