Low-density lipoprotein, or LDL, cholesterol is a contributing factor to the development of atherosclerosis. According to the book "Essentials of Medicine" by Carpenter, Griggs and Loscalzo, approximately 60 to 70 percent of a person's cholesterol levels are predetermined by genetics. Other contributing factors include age, sex, diet and activity levels.
LDL Cholesterol
According to the United States Department of Health and Human Services, LDL cholesterol is the main source of cholesterol build-up in the arteries. The main job of LDL is to transport cholesterol from the liver to cells of the body, states "Exercise Testing and Prescription" by David Nieman.
Atherosclerosis
Atherosclerosis develops in several different stages, according to Nieman. First, there is an injury to an arterial wall. This is more common than it sounds and can occur from hypertension, high cholesterol and high levels of oxidized LDL. When an injury occurs, the body reacts with its normal inflammatory response system. The response inflames the artery and sends white blood cells to help repair the situation. The white blood cells work to fix the injury by penetrating the inner layer of the artery and ingesting the localized LDL. The high presence of LDL attracts more white blood cells, which causes a greater narrowing of the artery. The ingested LDL forms a fatty streak inside the artery, which is a precursor to plaque. Plaque build-up can lead to heart attack or stroke.
Identification: Increased LDL
LDL cholesterol levels can be determined through blood analysis. LDL cholesterol is optimal when kept under 100 mg/dl, according to the National Heart Lung and Blood Institute. An LDL of 100 to 129 mg/dl is acceptable and anything over 139 mg/dl is considered high.
Identification: Atherosclerosis
Atherosclerosis can be tested using c-reactive protein levels in the blood. The American Heart Association states that c-reactive protein is an indicator of an inflammatory response inside the body, which can include the response of an arterial injury. A low-risk c-reactive protein level is 1.0 mg/L or less, 1.0 to 3.0 mg/L is average risk and anything above 3.0 mg/L is high risk.
Prevention and Treatment
You can prevent the development of high LDL and atherosclerosis with exercise and diet. Regular, moderate exercise is effective in lowering total cholesterol levels, according to "Essentials of Medicine." A healthy diet rich in fruits, vegetables and unsaturated fat can help you fight off atherosclerosis. Nieman states that a high intake of saturated fats and cholesterol and a low intake of fruits and vegetables have been linked to the development of oxidized LDL. If atherosclerosis is already developing, physical activity and diet can help, although there are many medications that can help delay the development and reduce LDL.
References
- "Essentials of Medicine"; Carpenter, Charles C.J., Griggs, Robert C., Loscalzo, Joseph, eds.; 2004
- "High Blood Cholesterol: What You Need to Know"; United States Department of Health and Human Services; 2005
- "Exericse Testing and Prescription"; Nieman, David C.; 2007
- National Heart Lung and Blood Institute: High Blood Cholesterol
- American Heart Association: Inflammation, Heart Disease and Stroke: The Role of C-Reactive Protein
