Most people focus their attention on ways of lowering cholesterol without ever really knowing what cholesterol is. While you certainly don't need to know, being able to answer the question "what is cholesterol?" may at least give you some better insights on why its important to keep it low, and how. If not, it may at least help prepare you for a spot on jeopardy.
What are the risks of high cholesterol? If you're like me and have really high cholesterol, you've probably asked yourself a number of questions such as; "What is my cholesterol level?", "How do I lower it?".
Cholesterol is quite simply a class of aerobic chemical compounds that are mostly hydrophobic in nature. So what the heck does that mean? Well, if you never took organic chemistry or biochemistry in college, or never went to college, it doesn't mean a whole lot. Even if you took those classes, it still doesn't tell you very much.
A better way to answer what is cholesterol is to focus on what it does. The chief purpose of cholesterol is to provide animal cell membranes with a fluid, flexible quality. Unlike plant cells, which are rigid, animal cells have to be able to bend and stretch without breaking. Animal cell membranes consist of two layers of lipids, each with a hydrophilic head and long, hydrophilic tail.
The heads orient themselves towards the watery cell interior, and the watery exterior of the cell, while the tails line up in the relatively water free center. Cholesterol, which is mostly hydrophobic, thus prefers being in the center area of the membrane, and is small enough to flow through this center area freely. The flow of cholesterol molecules through the interior areas of a cell membrane provides the membrane with flexibility.
Cholesterol is therefore vital to animal life. It is transported throughout the body in lipoprotein carriers that fall under a few different classes. The two general classes are high-density lipoproteins (HDL) and low-density lipoproteins (LDL). It is the LDL carriers that pose health risks in high levels by getting stuck along arteries, and not actually cholesterol.
When people ask me "What is cholesterol?"
that's usually what I tell them. I also tell them that it is an essential building block of several hormones, and is naturally produced by the liver. While our diets typically have plenty of cholesterol in them, the liver will naturally be able to meet all of our cholesterol needs without getting any from food. Therefore, you can never eat too little cholesterol. So, the next time someone asks you "what is cholesterol?" you know what to say.