Cholesterol is a component essential for health (cell membranes, steroid hormone production, vitamin D and bile salts, etc.). More than 75% of the body’s cholesterol comes from the synthesis of cholesterol, mainly by the liver. The remaining 25% comes from food. Cholesterol circulates in the blood in combination with proteins in the form of very fine droplets called lipoproteins. Depending on the nature of the proteins in each droplet, the main fractions of cholesterol that can be found are as follows: HDL or good cholesterol, LDL or bad cholesterol and other fractions. The interpretation of total cholesterol levels is not as useful as the interpretation of the other fractions (HDL, LDL, non-HDL, apolipoprotein B). See those specific results.