A blood test is the only way to measure cholesterol. High cholesterol levels in the blood lead to heart disease. More than 102 million American adults have high cholesterol, according to the Centers for Disease Control and Prevention. More than 35 million of these people have levels high enough to put them at increased risk for heart disease that could result in heart attack, stroke and other medical conditions, such as kidney disease.
Fastings
Fasting means you have nothing to eat or drink except for water for several hours before having your blood drawn. LabTestsOnline.org recommends you fast for nine to 12 hours before having your blood cholesterol tested. You should drink water to prevent dehydration. It can be more difficult to get blood from a dehydrated patient.
Types of Cholesterol
A medical laboratory measures several substances in the typical cholesterol test. Cholesterol is a waxy substance that isn't soluble in the watery plasma of blood. The body overcomes this by packaging cholesterol onto special lipoproteins such as LDL and HDL. LDL carries cholesterol to the blood cells and is most closely associated with heart disease. HDL carries excess cholesterol to the liver, where it's processed and eliminated from the body. Triglycerides are fat flowing through the bloodstream to provide instant energy to the cells of the body.
Lipid Profile
Your doctor orders a lipid profile, which is a panel of tests measuring total cholesterol, LDL, HDL and triglycerides. LDL and triglycerides are immediately sensitive to food and beverages. Food and drinks affect LDL and triglyceride levels. Triglycerides rise five to 10 times higher after eating, according to LabTestsOnline.org. Consumption doesn't immediately affect total cholesterol and HDL.
Smoking
Smoking increases LDL and triglycerides while decreasing HDL. Smoking may immediately affect blood chemistry, so you should not smoke while fasting for a blood test, according to St. Francis Outpatient Laboratories.
Alcohol
Triglycerides rise dramatically after the consumption of alcohol, and triglycerides remain high for several hours after. Do not drink alcohol for at least 24 hours before having your blood drawn for a cholesterol test.
Levels
Laboratories report cholesterol levels in milligrams per deciliter, or mg/dL. Lower levels of total cholesterol, triglycerides and LDL are healthier than high levels. Healthy total cholesterol measures 200mg/dL or less, and LDL should be lower than 100mg/dL. Your triglycerides should be less than 150mg/dL. High HDL levels are better than low levels. HDL of 60mg/dL or more offers the most protection for your heart. A man with HDL of 40mg/dL or less is at increased risk for heart disease, as is a woman whose HDL is 50mg/dL or lower.
