During a routine physical, your doctor may take a blood sample for a "lipoprotein profile," which measures your cholesterol and triglyceride (a type of fat that circulates in your blood) levels. This is an inexpensive and simple blood test, and it's recommended at least every five years for all adults starting at 20. (Individuals who are at risk for heart disease, such as those with a family history of heart disease, should be tested more often.) It's important to gain an understanding of this profile and learn whether you're at high risk for heart disease.

To get an accurate reading, you'll need to fast (abstain from consuming all food and beverages, except water) for nine to 12 hours before your blood is drawn. Otherwise, your results may be compromised by the types of food you have eaten. Having your blood drawn first thing in the morning is easiest; you can resume your normal meal plan for the rest of the day.

A lipoprotein profile shows:

• Total cholesterol
• HDL ("good") cholesterol
• LDL ("bad") cholesterol
• Triglycerides (blood fats)

Government and health organizations recommend the following cholesterol and triglyceride levels for the general public:

• Total cholesterol < 200 mg/dL
• LDL cholesterol < 100 mg/dL
• HDL cholesterol > 50 mg/dL for women, > 40 mg/dL for men
• Triglycerides < 150 mg/dL

Cholesterol and triglyceride levels that fall outside of this range are considered risk factors for heart disease. For individuals who have a higher risk for heart disease, such as those who have sustained a heart attack, the recommended ranges are set lower.

Modifying your lifestyle by reducing the amount of saturated fat and dietary cholesterol you eat, eliminating trans fat, and engaging in regular exercise — weight-healthy improvements outlined in the South Beach Diet — can go a long way to improve the results of your lipoprotein profile and, thus, lower your risk for heart disease. If you smoke, quitting will help raise your HDL. Be advised that heredity can be a factor in your test results (and your risk for heart disease), particularly with respect to LDL and triglyceride levels. Based on your specific circumstances, your doctor can recommend lifestyle changes, medication, or a combination of the two to control your cholesterol and triglyceride levels and lower your risk of heart disease.