Knowing the facts about cholesterol can reduce your risk for a heart attack or stroke. But understanding what cholesterol is and how it affects your health are only the beginning. You have to manage your cholesterol by taking prescribed medication or by a diet and lifestyle changes.
Cholesterol is a soft, fat-like, waxy substance found in the bloodstream and in all your body’s cells. It’s normal to have cholesterol. Cholesterol is an important part of a healthy body because it is used for producing cell membranes and some hormones. It also serves other needed bodily functions. But too much cholesterol in the blood is a major risk for coronary heart disease (which leads to heart attack) and for stroke. Hypercholesterolaemia is the medical term for high levels of blood cholesterol.
Cholesterol comes from two sources: your body and food. Your liver and other cells in your body make about 75% of blood cholesterol. The other 25% comes from the foods you eat.
Low-density lipoprotein (LDL) cholesterol is produced naturally by the body, but many people inherit genes from their mother, father or even grandparents that cause their bodies to produce too much of it. Eating saturated fat, trans fats and dietary cholesterol also increases the amount of cholesterol you have in your blood.
Cholesterol can’t dissolve in the blood. It has to be transported to and from the cells by carriers called lipoproteins, or LDLs, and is known as “bad” cholesterol. High-density lipoprotein, or HDL, is known as “good” cholesterol. These two types of lipids, along with triglycerides and Lp(a) cholesterol, make up your total cholesterol count, which can be determined through a blood test.
LDL (bad) cholesterol
If too much LDL (bad) cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that transport blood to the heart and brain. Together with other substances, it can form plaque − a thick, hard deposit that can narrow the arteries and make them less flexible. This condition is known as atherosclerosis. If a clot forms and blocks a narrowed artery, a heart attack or stroke can result.
HDL (good) cholesterol
About one-fourth to one-third of blood cholesterol is carried by high-density lipoprotein (HDL). HDL cholesterol is known as “good” cholesterol, because high levels of HDL seem to be a protection against heart attack. Low levels of HDL also increase the risk of heart disease. Medical experts are of the opinion that HDL tends to carry cholesterol away from the arteries and back to the liver, where it is processed to be passed out of the body. Some experts believe that HDL removes excess cholesterol from arterial plaque, slowing its build up.