AboutTodd Bublitz, RCEP Expertise I can answer questions on Cholesterol & Lipids, Cardiac Rehabilitation, and
preventive cardiology. I can also explain the risk factors for
cardiovascular disease and most cardiac diagnostic tests and procedures.
Experience
Professional Experience Former Lipid Clinic Coordinator for large Cardiology practice. Seventeen years experience in Cardiac Rehabilitation and risk factor modification. Researcher in cardiovascular exercise, cardiac function and cardiac testing.
Developed and maintain Lipid-Clinic.com
Also, Nuclear Cardiology Research Organizations National Lipid Association
American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR)
American College of Sports Medicine (ACSM)
Preventive Cardiovascular Nurses Association (PCNA)
Rocky Mountain Cardiopulmonary Rehabilitation Association (RMCRA)
Education/Credentials Registered Clinical Exercise Physiologist by ACSM Certified as 'Exercise Specialist' by ACSM
Question With regard to a full lipid cholesterol test, if I took the test right after eating would my LDL be higher or lower than if I fasted for twelve hours; would my HDL be higher or lower than if I fasted for twelve hours. Thank you very much for your response. Al Brown
Answer Al,
As you probably know, some of our lipid levels change dramatically after eating (or drinking anything with calories). The most effect is on the triglyceride level which can increase a very significant amount. A significant increase in triglyceride levels can cause a drop in the HDL level. Therefore, having a lipid test soon after eating can cause the HDL to be lower.
The actual level of LDL should not change significantly after eating. However, most labs use a calculation to estimate LDL levels. The formula is:
LDL=Total Cholesterol-(HDL+Triglycerides/5).
If you plug in "normal" values into this formula, you get the following:
LDL=200-(40+150/5)
LDL=130
If you plug in high triglycerides and low HDL you get the following:
LDL=200-(35+300/5)
LDL=105
As you can see, eating right before a lipid test can give you a false low LDL level.
Your doctor can ask the lab to do a "direct LDL" level - where the lab actually counts the LDL particles. If this were done, the LDL level would be accurate whether you've eaten or not.