Low-density lipoproteins, or LDL, combine fat and protein from food to protect nerve fibers and lubricate cell walls. These protein and fat molecules carry cholesterol through the bloodstream. Excess amounts of LDL can be associated with cholesterol building up within arterial walls, increasing the risk of cardiovascular disease. LDL levels less than 130 mg per dl are considered normal. High levels of LDL are considered to be a risk factor for coronary artery disease, notes Biology Online.
LDL in Excess is "Bad Cholesterol"
LDL particles contain about three-quarters of the cholesterol circulating in the body, reports Buffalo Cardiology & Pulmonary Associates. Up to 130 mg per dl of LDL is healthy and necessary for the body to function. Although it is often referred to as bad cholesterol, LDL is essential for cell repair. Every cell in your body is made partly of cholesterol, which is necessary for cell function, integrity and protection. LDL becomes known as "bad cholesterol" when blood serum levels exceed the American Heart Association's recommendation of 130 mg per dl.
Very Low-Density Lipoproteins Are Synthesized in the Liver
VLDLs, or very low-density lipoproteins, are protein-and-cholesterol-wrapped packages that contain triglycerides, which are molecules made up of fat and sugar. Most LDL begins as VLDL. These packages, or particles, are produced in the liver and sent to travel through the bloodstream to distribute the triglycerides to muscle cells. Triglycerides the muscles can't uptake are deposited in fat storage tissue. As the particles empty out their triglyceride cargo, they become progressively more dense, and lose the "V," as their density becomes low, but no longer very low.
Triglycerides Increase the Production of LDL
The need to process more triglycerides from excess saturated fat increases VLDL, and hence cholesterol, production, notes the Buffalo Cardiology & Pulmonary Associates. It also leads to more triglycerides circulating in the bloodstream, a risk factor for health problems. Triglycerides are formed from fats and blood sugars. These molecules combine with cholesterol to create lipoproteins. The body uses and stores fat in the form of triglycerides, but in order to use this energy the body must increase the amount of LDL in the blood. Additional LDL helps to transport this energy throughout the body. However, in excess, these fats can build up within the walls of the blood vessels.
Atherosclerosis is Associated With High Levels of LDL
Triglycerides help the blot to clot. Combining excess LDL and triglycerides over time allows the cholesterol that has built up within blood vessel walls to harden. When arteries and blood vessels become inflexible, blood has difficulty flowing through the body. The pressure of blood in the vessels and organs must be able to dilate and constrict to pump body throughout the body. Atherosclerosis is a condition in which the arteries harden and clog with fat. The National Institutes of Health notes that chemical therapy is required to combat the effects of this deteriorating condition. TLC, or therapeutic lifestyle changes, can combat the effects of increased cholesterol. With attention to diet and exercise, the body can break down some the fatty material in the arterial walls that will increase their flexibility.
Heart Attack Results From Long-Term High Levels of LDL
The National Institutes of Health suggests that LDL cholesterol rates lower than 70 mg reduce the risk of heart attack incurred by high LDL. Long-term high levels of LDL in the blood can clog and harden the arteries, disrupting blood flow to the heart. In addition to therapy with statins, which are medications that lower cholesterol levels, any attempt to modify saturated fat intake and increase exercise will reduce risk of heart attack. A 2004 report from the National Cholesterol Program recommends that physicians increase treatment for these individuals who are at higher risk for heart attacks. One of the recommended options included lowering the normal level of acceptable LDL in clients with high risk factors. The most notable risks factors for increased levels of LDL that lead to heart attack are smoking, hypertension, diabetes and metabolic syndrome.
