Cholesterol is a waxy, fat-like substance found in cell walls and vital to your body's testosterone, estrogen and vitamin D production, according to the Centers for Disease Control and Prevention. While the body naturally produces most of the necessary cholesterol, it also absorbs cholesterol from dietary sources. Cholesterol is measured in two forms: high-density lipoproteins, or good cholesterol, and low-density lipoproteins, or bad cholesterol. These numbers equal the total cholesterol level, which should be under 200 milligrams per deciliter for optimal health. Your LDL cholesterol should be under 130 mg/dL, and HDL should be around 60 mg/dL. Elevated cholesterol levels are a very serious health concern.
Atherosclerosis
When blood cholesterol levels are high, excess cholesterol can deposit on arterial walls, causing them to narrow and harden. When cholesterol deposits on the walls, it's referred to as plaque, and the buildup, which narrows the arteries, is called atherosclerosis.
Angina
Angina is pain caused by reduced arterial blood flow to the heart, or ischemia, the University of Maryland Medical Center explains. Atherosclerosis caused by elevated blood cholesterol levels is by far the most common cause of angina. Angina occurs in two types: stable and unstable. Stable angina most often occurs during exercise, and is treated with rest or prescription nitroglycerin. Unstable angina can occur at any time and is often a precursor to a heart attack. Angina pain is usually described as pressure, squeezing or tightness across the chest, and can be mistaken for heartburn, muscle strain or asthma.
Heart Attack
A heart attack, or myocardial infarction, occurs when arterial blood flow to the heart is blocked, preventing oxygen from reaching the heart. The heart muscle can die or become permanently weakened. Atherosclerosis is the primary cause of heart attacks, but can contribute to them in two different ways. Plaque buildup can be so severe that it cuts off blood flow to the heart from one of the coronary arteries. Plaque can also cause arterial walls to tear. When blood clots at the site of the tear, the clot can ultimately end up blocking arterial blood flow.
Stroke
There are two main types of strokes: ischemic strokes, caused reduced or absent blood flow to the brain, and hemorrhagic strokes, caused by leaking or burst blood vessels in the brain. Ischemic strokes account for more than 90 percent of strokes and are most often caused by atherosclerosis. Atherosclerosis can cause ischemic stokes two ways: by directly narrowing or blocking a cerebral artery, or by causing an arterial blood clot in another part of the body that then breaks off and travels to cerebral arteries and causes a blockage. The first example is known as a thrombotic stroke and the second as an embolic stroke.
