Most of us know that there is good and bad cholesterol in our body. Following is an excerpt from a local newspaper that clearly explains the difference between them. I found it very educational and hence thought of sharing it here. Q: Since cholesterol is a single molecule, how can it be "good" and "bad?" A: You are correct in that the cholesterol molecule itself isn't inherently good or bad. Cholesterol is a soft, waxy substance found in the blood stream and in the body's cells. It's essential for good health and serves several functions, including the formation of cell membranes and certain hormones. Our bodies couldn't survive without it. What makes cholesterol good or bad isn't the molecule itself, but the type of protein particle that is carrying the cholesterol in the blood stream. When low-density lipoprotein, or LDL, particles pick up cholesterol, they carry cholesterol from the liver to the other parts of the body. This function is essential to good health. But if there are too many particles, problems arise, because the LDL carriers start to store the cholesterol in arteries throughout the body, causing buildup. So if a cholesterol test measures a high level of LDL particles in your blood, that means too much cholesterol is being moved and stored in your arteries, putting you at risk for heart disease. Now, if cholesterol is picked up by a high-density lipoprotein, or HDL, particle, it's a good thing. That's because the HDL particles scavenge excess cholesterol in the blood stream and carry it back to the liver so it can be eliminated from the body. If a blood test finds a lot of HDL particles, that means you've got a strong cleanup crew taking care of excess cholesterol. If your HDL levels are too low, that means there aren't enough particles available to help dispose of excess cholesterol.