What is high cholesterol? Cholesterol is a type of fat, or lipid, which is important for a variety of functions in your body. Your body needs cholesterol to make cell membranes, bile acids, and certain hormones. There are two main sources of cholesterol. Your body makes most (75%) of the cholesterol found in your blood. The rest (25%) comes from the foods you eat in the form of animal products. High cholesterol, or hypercholesterolemia, is caused by ingesting too much cholesterol in your diet or by your body making too much cholesterol. There are two main types of cholesterol: “bad” cholesterol, also known as low-density lipoprotein (LDL), and “good” cholesterol, also known as high-density lipoprotein (HDL). When too much LDL is present in your blood, it can build up in a substance called plaque on the walls of the arteries and increase the risk of developing cardiovascular diseases. These include atherosclerosis, coronary heart disease, blood clots, heart attack, and stroke. In contrast, HDL helps prevent LDL from clogging your arteries. Higher levels of HDL help reduce your risk of heart disease, heart attack, and stroke. Triglycerides are another type of fat that is included in determining your risk of heart disease, heart attack, and stroke. When HDL, LDL and triglycerides are present in the right levels and balance in the body, cholesterol functions to protect your health including cardiovascular health. In the United States, approximately one in every six adults has elevated total cholesterol levels, defined as 240 mg/dl (milligrams per deciliter blood) and higher (Source: CDC). There are generally no symptoms of high cholesterol and many people do not realize they have it. This means that many U.S. adults do not realize they have an increased risk of heart disease, heart attack, and stroke. In addition, heart disease and stroke are the leading causes of death in the United States. More than a million people in the United States have a heart attack each year and many of them die. (Source: NHLBI). Considering the health risks of high cholesterol, it is important to get a cholesterol-screening panel or test at regular intervals. If you know your risks, you can help control them through diet, exercise, lifestyle changes, regular medical care, and sometimes medications. High cholesterol is associated with an increased risk of cardiovascular disease, which includes heart attack and stroke. Seek immediate medical care (call 911) if you, or someone you are with, have symptoms of a stroke or heart attack, such as chest pain, difficulty breathing, dizziness, sweating, fainting, anxiety, sudden numbness or weakness, confusion, trouble speaking or understanding speech, trouble seeing or walking, or severe headache.