Fasting Rules for Cholesterol Testing

A cholesterol test is a routine test doctors use to measure the amount of cholesterol in the bloodstream. The test, which requires a blood sample, helps determine if a patient is at a high risk for stroke, heart attack or other health problems. This test is most accurate if performed after a fast, but can also provide beneficial information without fasting.

Test Results

A cholesterol test will produce three numbers: the HDL, LDL and overall cholesterol. When a patient takes the test without fasting, the HDL and overall cholesterol will be accurate, but one can only get an accurate LDL level when fasting. The American Heart Association states a healthy overall cholesterol level is 200 mg/dL or lower. HDL cholesterol is known as a good cholesterol and can actually help prevent heart diseases. The American Heart Association recommends that everyone aims to keep their HDL cholesterol above 40 mg/DL. LDL cholesterol is known as bad cholesterol. It can clog arteries and lead to heart disease. LDL levels below 100 mg/dL are considered healthy.

Fasting Rules

A doctor may have asked the patient to fast before having a cholesterol test. Fasting for 9 to 12 hours prior to a test will give the most accurate test results for LDL levels as they can be affected by the food one eats. This means someone taking a cholesterol test must abstain from eating, drinking and taking medication starting at least 9 hours before taking the test. It will be easiest to do this if the blood test is scheduled first thing in the morning.

Fasting Benefits

If a patient taking a cholesterol test does not fast and the cholesterol levels are high, the doctor may require him or her to take the test again. Although the HDL and overall cholesterol readings will be accurate, a doctor will want to know the LDL level so he can make proper recommendations to lower cholesterol levels.

Testing Frequency

The National Heart Lung and Blood Institute recommends anyone over age 20 get a fasting cholesterol test every five years. Some people are at a higher risk for having high cholesterol. Age, gender and family history can change the risk for high cholesterol. For patients who are at a higher risk, a doctor may recommend a different testing schedule.

Improving Cholesterol Levels

For patients whose cholesterol levels are high, there are multiple ways to bring them back to healthy levels. Healthy eating and regular exercise, along with prescription medicines prescribed by a doctor can help regulate cholesterol and help the patient to avoid related health problems.