What Is Cholesterol?

Cholesterol is a soft, fat-like substance. It is a building block of body cells and hormones, makes up 50 percent of your nervous system, and is necessary for metabolism. In moderate amounts, it is essential to good health. But the dangers of high cholesterol, including artery blockage and damage, are well-documented. Other studies suggest that very low cholesterol levels can also be harmful and dangerous. The key seems to be making sure your body has enough—but not too much.

Cholesterol comes from two sources:
  1. Serum (blood) cholesterol flows through the bloodstream. Your body manufactures most of its blood cholesterol, but it absorbs some from the foods you eat. A total blood cholesterol level of less than 200 mg/dL is a healthy goal.
     
  2. Dietary cholesterol is found only in foods of animal origin, such as meat, poultry, fish, eggs, and dairy products. It is not found in plant foods. This source is easier to control. Individuals should limit their intake of cholesterol to less than 300 milligrams daily.
Knowing Your Numbers
It might seem obvious, but it can’t be emphasized enough. One of the best ways to lower your cholesterol is to track it. Have your doctor perform blood tests regularly so that you can both track your results and progress.

A complete cholesterol pictures is made up of three different things:
  • HDL (High Density Lipoprotein) is the good, Healthy cholesterol. HDL picks up and carries excess cholesterol from artery walls and brings it back to the liver for processing and removal. You want this number to be high—at least 60 mg/dL—to protect your heart. Levels too low (less than 40 mg/dL) are bad for your health, increasing your risk for heart disease.
     
  • LDL (Low Density Lipoprotein) is the bad, Lazy cholesterol. LDL is made by the liver to carry cholesterol to the body’s cells and tissues. It may form deposits on the walls of arteries and other blood vessels. You want this number to be low. Less than 100 mg/dL is optimal (and up to 129 mg/dL is near optimal). Unhealthy levels are 130-159 mg/dL (borderline high), 160-189 mg/dL (high), and over 190 mg/dL (very high).
     
  • Triglycerides are the most common forms of fat found in food and in the body. The visible fat on chicken and steak is actually triglycerides. If you are overweight, your body stores the extra calories you eat as triglycerides. People with high triglyceride levels often have low HDL (good cholesterol) levels; this combination is considered by many experts to be associated with an increased risk for heart disease. Less than 150 mg/dL of triglycerides is considered normal. Levels above 150 are considered high to different degrees: 150-199 mg/dL (borderline high), 200-499 mg/dL (high) and over 500 mg/dL (very high).

High cholesterol, heart disease and obesity are the familiar steps in a tragic progression of declining health that affects hundreds of thousands of people every year.
  • Nearly 1 million Americans died of heart disease in 2002.
  • 52 million Americans have high cholesterol, a leading cause of heart disease.
  • 67 percent of Americans are overweight or obese, the top contributor to high cholesterol.
  • According to the American Heart Association, being overweight or obese is the #2 preventable cause of death in the United States.
The relationship is clear. For a healthy heart, the best course of action is often to lower cholesterol in large part by losing weight. Even without weight loss, there are many heart benefits to lowering your cholesterol levels.

Be sure to work with your doctor to develop a cholesterol-lowering plan that is safe and effective for you. These plans usually involve some combination of dietary changes, regular exercise, medication, and weight loss.