Cholesterol is a soft, waxy substance found among the lipids (fats) in the bloodstream
             and in all your body's cells. It's an important part of a healthy body because it's used to
             form cell membranes, some hormones and other needed tissues. But a high level of
             cholesterol in the blood - hypercholesterolemia - is a major risk factor for coronary
             heart disease, which leads to heart attack.
             Cholesterol and other fats can't dissolve in the blood. They have to be transported to
             and from the cells by special carriers called lipoproteins . There are several kinds, but
             the ones to be most concerned about are low-density lipoprotein (LDL) and
             Low-density lipoprotein is the major cholesterol carrier in the blood. If too much LDL
             cholesterol circulates in the blood, it can slowly build up in the walls of the arteries
             feeding the heart and brain. Together with other substances it can form plaque, a thick,
             hard deposit that can clog those arteries. This condition is known as atherosclerosis . A
             clot (thrombus) that forms in the region of this plaque can block the flow of blood to part
             of the heart muscle and cause a heart attack. If a clot blocks the flow of blood to part of
             the brain, the result is a stroke. A high level of LDL cholesterol (more than 130 mg/dL)
             reflects an increased risk of heart disease. That's why LDL cholesterol is often called
             "bad" cholesterol. Lower levels of LDL cholesterol reflect a lower risk of heart disease.
             About one-third to one-fourth of blood cholesterol is carried by high-density lipoprotein
             or HDL. Medical experts think HDL tends to carry cholesterol away from the arteries
             and back to the liver, where it's passed from the body. Some experts believe HDL
             removes excess cholesterol from atherosclerotic plaques and thus slows their growth.
             HDL cholesterol is known as "good" cholesterol because a high level of HDL seems to
             protect against heart attack. The opposite is also tr...