Cholesterol: The Good, the Bad, and Keeping it in Check

With obesity at epidemic levels in the U.S, and heart disease and stroke major causes of death or serious injury, cholesterol should be better kept in check than it is. The American public tends to be aware of the dangers that lipids such as cholesterol cause to the body, yet cholesterol itself is still somewhat of a mystery that is never fully understood. Where does cholesterol come from? What is the difference between good and bad cholesterol? What illnesses can unhealthy levels of both good and bad cholesterol lead to? Most of all, how can one change their lifestyle in order to improve both good and bad cholesterol levels?

We'll start with the topic of cholesterol in general. Without breaking it down into its separate categories, cholesterol is a fat-like substance that is found in both the bloodstream and in the body. Contrary to popular belief, cholesterol is necessary in order to survive as it is used to create the cell membrane in body cells, as well as various hormones. However, the fact that cholesterol is found naturally in the body doesn't mean that it doesn't pose a threat. In fact, too much cholesterol poses serious health risks to the human body. The American Heart Association (2007), notes that nearly 75 percent of cholesterol is produced by the body, and another 25 percent is gained through the foods we consume. Furthermore, depending on the type of cholesterol consumed and found in greater quantities in the body, one's health may be very good, or very poor.

There are four different types of cholesterol found in the human body: low density lipoprotein (LDL), high density lipoprotein (HDL), triglycerides, and Lp(a) cholesterol. The combination of these four cholesterols make up the total amount of cholesterol in the body. LDL is considered the bad cholesterol; it is the form that, in excess, can cause arterial clogs and increase one's risk of heart attack and stroke. Build ups of LDL can clog arteries leading to the heart and brain. Additionally, LDL build up in conjuction with other body substances can cause the arteries to harden with plaque, a condition caused atherosclerosis. LDL can be inherited, produced naturally in the body, and consumed in the form of saturated fats, trans fats, and dietary cholesterol (American Heart Association, 2007). A Framingham study found that lowering LDL levels significantly reduces the risk of coronary heart disease (1984)* Thus, lowering one's LDL levels is key in reducing the risk of heart disease.

Lp(a) is a variation of LDL and high levels generally indicate a development of fatty build up in the arteries. It is thought that Lp(a) interacts in some way with the artery creating the fatty build ups that lead to clogged arteries, and associated problems (American Heart Association, 2007).

HDL is considered the good cholesterol and is thought to actually prevent against heart attacks and strokes. According to the American Heart Association (2007) "HDL tends to carry cholesterol away from the arteries and back to the liver, where it is passed from the body." Around a quarter of blood cholesterol is HDL cholesterol. Despite all the praises for HDL, excessively high HDL can also have a downside. According to Doctor Singh (2006), "Very high levels of HDL cholesterol has also been reported to be atherogenic." Singh also goes on to explain that this contradictory phenomenon is not understood, yet it is still something to watch out for.

Triglycerides are fats made in the body and high triglyceride levels are generally due to poor eating and lifestyle habits, including high alcohol consumption, high carb diets, and low physical activity levels. Physical activity can help reduce triglyceride levels because triglycerides provide a significant portion of body energy during aerobic activities (Chiras, 2005). This is also the reason why aerobic exercise is so important when one is trying to lose weight. High triglycerides are often found in individuals who are obese, have diabetes, and have or are at risk for heart disease and other heart problems (American Heart Association, 2007). Despite this, triglyceride levels should not be excessively low either, as mentioned earlier, fatty deposits around the body aid in cushioning organs, provide energy, and help to create the cell's membrane.

Managing cholesterol

One of the most important changes a person with high blood cholesterol can make are lifestyle changes. Following a healthy diet by reducing high fat and high carbohydrate intake can help to reduce LDL levels; especially reducing trans fats and saturated fats. Lifestyle changes also include reducing alcohol intake and reducing or altogether quitting smoking. Additionally, adding activity to one's daily routine in the form of exercise of similar activities can help to burn off excess triglycerides and thus aid in reducing the risk of atherosclerosis and coronary heart disease. The American Heart Association recommends 30 minutes of exercise a day, and notes that breaking up activities into 10 or 15 minutes sessions would be just as effective as doing it all at once (2007).

An individual with high cholesterol can also turn to their doctor for medication recommendations. These should be taken as instructed by a person physician, and be coupled with exercise and a healthy diet. Medication alone, without lifestyle changes, isn't likely to do much good in significantly reducing the risks of high cholesterol.

References:

American Heart Association. (2007). About Cholesterol. Retrieved February 17, 2008, from http://www.americanheart.org/presenter.jhtml?identifier=512

Chiras, D., D. (2005). Human Biology, 5^th Edition. Sudbury, Mass. Jones and Bartlett Publishers.

National Heart Lung and Blood Institute. (N.d). The Cholesterol Heart Disease Connection. Retrieved February 17, 2008, from http://nhlbisupport.com/chd1/chdexp1.htm

Singh, V., N. (2006). High HDL Cholesterol. Retrieved February 17, 2008, from http://www.emedicine.com/Med/topic1061.htm

*Found on National Heart Lung and Blood Institute.