Cholesterol testing helps gauge your risk for heart disease, the number-one killer of American men and women, notes the American Heart Association. Unhealthy levels of cholesterol are detectable by lipoprotein profile blood testing. This blood test requires fasting beforehand, which helps give the most accurate assessment of your complete cholesterol health.
Cholesterol
Cholesterol, a waxy lipid naturally made by your body, is critical to normal cell function. The body makes enough cholesterol on its own, but your diet introduces more into your system. When too much cholesterol is in your system, the potential for artery narrowing and hardening increases. This can negatively affect blood flow to important tissues and organs, such as the heart and brain, and put you at greater risk for heart disease and stroke.
Types of Cholesterol Measured
Cholesterol testing can measure not only total cholesterol counts, but specific cholesterol factors that help gauge your risk for heart disease. Cholesterol is carried through the blood by lipoproteins. Low-density lipoprotein or LDL cholesterol is considered unhealthy because it increases buildup on artery walls. High-density lipoprotein or HDL cholesterol helps keep LDL from clogging artery walls and transports it to the liver for removal. Triglycerides are not a type of cholesterol but another fatty lipid that is measured along with cholesterol. Often, high triglycerides are associated with high cholesterol; both increase your risk for heart disease.
Cholesterol Testing and Fasting
If you go to your doctor's office without fasting beforehand, blood testing can provide reliable results for total cholesterol and HDL levels. Both of these can indicate your risk of heart disease, but they don't give the total picture. Lipoprotein profile testing gives measurements of HDL, total cholesterol, LDL and triglycerides -- a better overall picture of your cholesterol health. Recently consumed foods can affect readings of LDL and triglyceride levels, so for lipoprotein profile testing you should fast nine to 12 hours before the test. This means no food, drink or medications, only water. Alcohol can cause triglyceride levels to spike excessively, so it's best to avoid drinking alcohol for 24 hours before testing, too.
Recommendations and Tips
Optimal total cholesterol should be less than 200 mg/dL, while LDL should fall below 100 mg/dL. Triglyceride readings should be below 150 mg/dL for optimal health. HDL levels, however, are best at higher levels since they help remove cholesterol from the tissues; a level above 40 mg/dL is good, but levels above 60 mg/dL decrease your risk for heart disease. The National Cholesterol Education Program guidelines suggest that every adult, starting at 20 years old, have lipoprotein profile cholesterol testing every five years. If you've changed your diet because of high cholesterol, your cholesterol levels may show positive changes in two to four weeks; however, improvements may not be fully reflected in cholesterol testing for up to three months.
References
- American Heart Association; Populations; 2011
- Harvard Health Publications: Which Cholesterol Test Should You Get?
- National Cholesterol Education Program; Third Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III): Executive Summary; 2001
- American Heart Association: About Cholesterol
- American Heart Association: How to Get Your Cholesterol Tested
- University of Iowa Hospital & Clinics; Risk Factors for Heart Disease: Frequently Asked Questions; William Haynes, M.D.; January 2004
