Cholesterol is a waxy, fat-like substance located in cells of the body and the bloodstream, according to the National Heart, Lung and Blood Institute. The body needs cholesterol to build and maintain healthy cells. High blood cholesterol levels cause fatty deposits to accumulate within blood vessels, however. Eventually, this accumulation prohibits an adequate amount of blood to flow through the arteries, potentially leading to heart attack or stroke.
Mechanism
Cholesterol attaches to a protein and is carried through the blood. Together, the cholesterol and protein form a lipoprotein. There are three different types of proteins cholesterol can attach to, making the following formations: low-density lipoprotein, very-low-density lipoprotein and high-density lipoprotein. Low-density lipoprotein, or LDL, is termed "bad" cholesterol since it causes an accumulation of cholesterol within the arterial walls, making them hard and narrow.
Very-low-density lipoprotein, or VLDL, contains several triglycerides, which is a type of fat. VLDL causes LDL to swell in size, causing blood vessels to narrow further.
High-density lipoprotein, or HDL, is termed "good" cholesterol since it picks up excess cholesterol in the bloodstream and brings it back to the liver for excretion.
Risk Factors
Smoking, high blood pressure, poor diet and a sedentary lifestyle puts people at greater risk of having high blood cholesterol levels. Cigarette smoking and high blood pressure causes increased pressure on the arterial walls, damaging them and making more susceptible to fatty deposits, according to the MayoClinic.com.
People who consume foods high in cholesterol, such as red meat and full-fat diary products, are also at risk as these foods raise total blood cholesterol levels. Sedentary people are at greater risk than regular exercisers, because exercise increases the body's HDL, while lowering the LDL, according to MayoClinic.com.
Complications
High blood cholesterol levels can cause atherosclerosis, a condition in which dangerous amounts of cholesterol and other deposits accumulate within the arterial walls. Together, cholesterol and other deposits, termed plaque, can reduce and restrict blood flow through the arteries, causing complications such as heart attack and stroke.
If plaque tears or ruptures, a blood clot can form at the rupture site, causing a blockage of blood flow. Inadequate blood flow through certain arteries can prevent the heart from receiving enough oxygen-rich blood, thus increasing your risk for heart attack. Additionally, a lack of blood flow to brain can cause a stroke.
Tests and Treatment
Blood cholesterol levels can be measured via a blood test, called a lipid profile. Lipid profiles report total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides. Refrain from eating or drinking 12 hours prior to your blood test in order to obtain the most accurate measurements.
The main goal of reducing blood cholesterol levels is to lower LDL enough to decrease people's risk of atherosclerosis, heart attack and stroke, according to the National Heart, Lung and Blood Institute. People can reduce LDL via lifestyle changes, such as physical activity, dietary restrictions and weight management. If lifestyle changes are insufficient, cholesterol-lowering medication may be prescribed.
