How is cholesterol related to heart disease?
The Framingham Heart Study established that high blood cholesterol is a risk factor for coronary heart disease (CHD). Results of the Framingham study showed that the higher the cholesterol level, the greater the CHD risk. On the other end of the spectrum, CHD is uncommon at total cholesterol levels below 150 milligrams per deciliter (mg/dL). A direct link between high blood cholesterol and CHD has been confirmed by the Lipid Research Clinics-Coronary Primary Prevention Trial (1984) which showed that lowering total and LDL (“bad”) cholesterol levels significantly reduces CHD. A series of more recent trials of cholesterol lowering using statin drugs have demonstrated conclusively that lowering total cholesterol and LDL-cholesterol reduces the chance of having a heart attack, needing bypass surgery or angioplasty, and dying of CHD-related causes. Recent studies have shown that cholesterol lowering in people without heart disease greatly reduces their risk for developing CHD, including hea
A certain form of cholesterol called low-density lipoprotein (LDL) cholesterol causes fat, known as plaques, to deposit on the walls of the arteries. This builds up gradually over the course of 20 or 30 years, usually beginning in early adulthood. As the plaques deposit, the walls of the arteries harden and weaken, reducing the flow of blood through the artery. The extent of the problem and how quickly it develops depends on the amount of low-density lipoprotein (LDL) cholesterol in the blood. The build up of plaque eventually damages the lining of the artery, causing blood cells called platelets to stick to the surface in the form of a clot. This can narrow the artery considerably and cause a form of chest pain known as unstable angina. This condition may mean that you can only walk a few steps before feeling chest pain and you should see you doctor at this point. Sometimes the plaque becomes covered by scar tissue, which can rupture under any sudden stress. This creates a wider area
Generally speaking, high levels of LDL (bad cholesterol) are associated with increased risk of developing coronary heart disease, whereas high levels of HDL (good cholesterol) are associated with decreased risk. One of the main ways in which LDL cholesterol levels in the blood can become too high is through eating too much saturated fat and cholesterol in the diet. Other factors also affect blood cholesterol levels, such as genetics, age and gender. High blood cholesterol levels contribute to increased risk of heart disease. There are also several other risk factors, including cigarette smoking, high blood pressure, diabetes, obesity, and physical inactivity. Any of these, in addition to high blood cholesterol, further increases the risk of heart disease. LDL cholesterol collects in the walls of arteries (especially the coronary arteries which supply the heart), which leads to accumulation of cholesterol-laden “plaque” in vessel linings. This condition is called atherosclerosis or “har
