Lipids: Another word for "fats", are an important part of living cells. Together with carbohydrates and proteins, lipids are the main constituents of plant and animal cells. Cholesterol - Cholesterol is a substance (a steroid) that is essential for life. It forms the membranes for cells in all organs and tissues in your body. It is used to make hormones that are essential for development, growth and reproduction. It forms bile acids that are needed to absorb nutrients from food. A small amount of your body's cholesterol circulates in the blood in complex particles called lipoproteins. These lipoproteins include some particles that carry excess cholesterol away for disposal (see HDL, good cholesterol) and some particles that deposit cholesterol in tissues and organs (see LDL, bad cholesterol). Cholesterol levels fluctuate over time. The measured cholesterol level may differ by as much as 10% from one month to another. It may go up sometimes or it may go down sometimes. These changes are called biological variation and they represent normal variability inherent in human metabolism. High cholesterol may be the result of an inherited disease or it may result from a diet high in saturated fats. For many people it is caused by a combination of both a high fat diet and an inherited tendency towards high cholesterol. All adults over the age of 20 should have a cholesterol test at least once every five years. HDL cholesterol - One of the classes of lipoproteins that carry cholesterol in the blood. HDL is considered to be beneficial because it removes excess cholesterol and disposes of it. Hence HDL cholesterol is often termed "good" cholesterol. |
