Cholesterol is a fat-like, waxy substance that can be found in all parts of your body. It aids in the production of cell membranes, many hormones, and vitamin D. The cholesterol in your blood comes from two sources: the foods you eat and your liver. However, your liver makes all the cholesterol your body needs.
Cholesterol and other fats are transported in your blood stream in the form of spherical particles called lipoproteins. The two most commonly known lipoproteins are low-density lipoproteins (LDL) and high-density lipoproteins (HDL).
What is LDL (low-density lipoprotein) cholesterol?
What is HDL (high-density lipoprotein) cholesterol?
Low-density lipoprotein (LDL), or "bad" cholesterol, is a type of fat in the blood that contains the most cholesterol. It can contribute to the formation of plaque buildup in the arteries, known as atherosclerosis, which is linked to increased risk of heart attack and stroke.
You want your LDL to be low. To help lower it:
High-density lipoprotein (HDL), or "good" cholesterol, helps to remove cholesterol from the blood, preventing the fatty buildup and formation of plaque.
You want your HDL to be as high as possible. Some people can raise HDL by:
For others, medicine may be needed. Because raising HDL is complicated, you should work with your physician on a therapeutic plan.
A cholesterol screening is an overall look at, or profile of, the fats in your blood. Screenings help identify people at risk of heart disease. It is important to have what is called a full lipid profile to show the actual levels of each type of fat in your blood: LDL, HDL, triglycerides, and others. Consult your physician regarding the timing of this test.
High blood cholesterol is a significant risk factor for heart disease and stroke. Lowering blood cholesterol through increased physical activity, weight loss, smoking cessation, and proper diet lowers that risk. Blood cholesterol, however, is very specific to each individual and, for that reason, a full lipid profile is an important part of your medical history and important information for your physician to have. In general, healthy levels are as follows:
LDL—less than 100 milligrams per deciliter (mg/dl) is considered desirable
HDL—greater than 40 milligrams per deciliter (mg/dl)
A total cholesterol level below 200 mg/dl is considered desirable
In some individuals who already have coronary artery disease (CAD) and/or who have an increased number of risk factors for coronary heart disease, a physician may determine that the LDL cholesterol level should be kept lower than 130. Recent studies have shown that those who are at highest risk for a heart attack should lower their LDL cholesterol level to less than 100, and that an LDL cholesterol level of 70 or less may be optimal for those individuals at the very highest level of risk. Always consult your physician for a diagnosis.
Medical treatment may include:
Modification of risk factors. Some risk factors that can be changed include lack of exercise and poor dietary habits.
Cholesterol lowering medications. Medications are used to lower lipids (fats) in the blood, particularly low-density lipoprotein (LDL) cholesterol. Statins are a group of antihyperlipidemic medications, and include simvastatin (Zocor), atorvastatin (Lipitor), and pravastatin (Pravachol), among others. Bile acid sequestrants—colesevelam (Welchol), cholestyramine (Questran), and colestipol (Colestid)—and nicotinic acid (niacin) are two other types of medications that may be used to reduce cholesterol levels.
Elevated cholesterol is a risk for many Americans. Consider these statistics:
According to the American Heart Association, about 99 million American adults have total blood cholesterol levels of 200mg/dl and higher, and of those about 32 million American adults have level of 240 or above.
Elevated cholesterol levels early in life may play a role in the development of adult atherosclerosis.
According to the American Heart Association, high blood cholesterol that runs in families will affect the future of an unknown (but probably large) number of children.
Triglycerides are another class of fat found in the bloodstream. The bulk of your body's fat tissue is in the form of triglycerides.
The link between triglycerides and heart disease is under clinical investigation. However, many people with high triglycerides also have other risk factors such as high LDL levels or low HDL levels.
A healthy triglyceride level is less than 150 mg/dl. Elevated triglyceride levels may be caused by medical conditions such as diabetes, hypothyroidism, kidney disease, or liver disease. Dietary causes of elevated triglyceride levels may include high intake of alcohol, and foods containing cholesterol, saturated fat, and trans-fat.