Lipid disorders are abnormalities in the amount of fatty substances, called lipids, in the blood. Cholesterol and triglycerides are two types of lipids measured. These lipids are involved in many body processes.

High cholesterol levels are associated with an increased risk of coronary heart disease , hardening of the arteries (atherosclerosis), and stroke . A total cholesterol level of less than 200 milligrams per deciliter (mg/dl) is desirable, 200-239 mg/dl is borderline high, and over 239 mg/dl is high.

Plaque Due to Build-up of Lipids in an Artery

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There are two main types of cholesterol:

  • High-density lipoprotein (HDL) cholesterol —This is often referred to as the "good" cholesterol, which helps protect against heart disease. It is believed to carry cholesterol to the liver and away from arteries. Levels of 60 mg/dl or higher are beneficial in lowering heart-disease risk.
  • Low-density lipoprotein (LDL) cholesterol —This is often referred to as the "bad" cholesterol, which increases the risk of heart disease. High levels allow plaque to build up in your arteries. Levels less than 100 mg/dl are considered optimal.

Triglycerides also contribute to heart disease in some people. Levels above 199 mg/dl are considered high and may require treatment.

Factors such as heredity, certain drugs and diets high in saturated fat, can lead to unhealthy elevations in lipid levels. Large amounts of carbohydrates or alcohol may also lead to high lipid levels.

According to the American Heart Association, 105 million Americans have a total cholesterol of 200 mg/dl or higher. Certain diseases such as diabetes mellitus, hypothyroidism, or the nephotic syndrome can be associated with elevated lipid levels.