cholesterol



For years, cholesterol has been a major concern for millions of people around the world. This fear of cholesterol has led to many consultations with specialists like physicians and nutritionists. It seems that there is a great misconception about this molecule. A majority of the population is conscious of the harm that it can cause, but they are not aware that it has pertinent values to our body. There are two major forms that cholesterol comes in: 1) low density lipoprotein, which is generally considered "bad" cholesterol and 2) high density lipoprotein, which is known as "good" cholesterol. Although given these names, there is nothing inherently good or bad about them. This research will clarify a lot of the misconceptions that are associated with cholesterol and the overall effect that cholesterol has on the human body.
Cholesterol is a soft, fat like substance made up of carbon, hydrogen, and oxygen, that is found in all the body\'s cells and is used to form cell membranes, manufacture hormones and other necessary substances. It is an organic compound belonging to the sterol family that also encompasses steroids.
Cholesterol is produced two ways. The first is by the liver. "The liver produces about 50,000,000,000,000,000 cholesterol molecules a second" (Body Mechanics 1), or about 1,000 mg of cholesterol a day. The second is by the intake of the foods eaten like animal fats (saturated and polysaturated fats) such as cheese, lard, egg yolks, red or marbled meat, pork, processed meat, gravies, palm or coconut oil, deep fried foods, whole milk, butter, etc.. This second process is accountable for another 400 mg - 500 mg of cholesterol a day.
Once eaten, the cholesterol in the food goes into the intestines to await digestion. "Chylomicrons (fatty particles containing mainly triglycerides, but also cholesterol, phospholipids and protein) are produced in the intestinal wall" (Arthersclerosis 3). Once the chylomicrons enter the bloodstream, they bind to receptors on the capillaries. A large percentage of triglycerides is broken down and released into circulation. "The remainder of the chylomicron (the \'chylomicron remnant\'), now richer in cholesterol, continues in circulation until it reaches the liver and is absorbed (Athersclerosis 3). Since cholesterol is like a fat, it is hydrophobic and unable to mix with water or blood. In order for it to be carried through the blood, the liver the combines the cholesterol with triglycerides and proteins (called lipoproteins) to form packages called very low density lipoproteins (VLDL). These packages, which account for 10-15 percent of the cholesterol in the body, are dispersed into the bloodstream and are "transported to tissue capillaries where triglycerides are broken down and either used for energy or stored by muscle or fat cells" (Athersclerosis 3). After the release of the triglycerides, the package now has a higher percentage of cholesterol. This package is now called low density lipoproteins or "LDL".
LDL\'s, also known as the "bad" cholesterol, is transported through the bloodstream to build cells, make hormones, and act as an insulation for nerves. Low density lipoproteins account for "60-70 percent of the total serum cholesterol" in the body (ATP: Chapter 1 1). This package of cholesterol is very useful to the body. It is necessary in the membranes of cells. If the cell gets too cold, the cholesterol kept the cell from freezing or turning solid. Conversely, as the cell gets too hot, the cholesterol keeps the cell from melting. This so called "bad" cholesterol, maintain the cell\'s fluidity. Once the LDL\'s have completed their tasks, they are removed from the body though the bloodstream to the liver. However, this removal process can occur at slower rates in certain people than others. This causes a build up of the cholesterol within the walls of the arteries. This build up, over time, can slow down or even prevent the circulation of blood to the heart and brain and can cause such disorders as Atherosclerosis, in which "deposits of cholesterol and other fatty substances circulating in the blood accumulate in the interior walls of the blood vessels", and hypercholesterolemia, which is an elevated level of cholesterol in the blood, and ultimately coronary heart disease (CHD), which causes heart attacks (Britannica Online 1). This is where the LDL\'s get their "bad" reputation.

In addition to VLDL\'s and LDL\'s, there is another form of