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Old 03-23-2015
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Question Cholesterol level fasting vs postprandial

Dr Turco in Kaplan Biochem videos says that it's important to measure cholesterol level after overnight fasting because of transient hypercholesterolemia 2-7 haours after eating. On the other hand Goljan RR says that because chylomicrons contain very little cholesterol eating doesn't affect cholesterol level so fasting isn't required.

Can anyone help to make it clear?
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Old 03-23-2015
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Idea!

What I can think of is the following:

Serum cholesterol is a very general term in medicine. the USPSTF recommends first a non-fasting cholesterol (cheap) level for a general idea. If elevated you should do a fasting cholesterol level (to check LDL NOT cholesterol)

Now, if you double check your Goljan, it says that the main carrier for cholesterol in the serum is LDL (Also, LDL is the ONE responsible for the vascular damage, NOT serum cholesterol). To get an accurate LDL level you must be fasting as chylomicrons falsely decrease the amount of LDL=Cholesterol-HDL-{(TG/5) this is VLDL}. Chylomicrons falsely increase VLDL which causes the decrease in LDL

So, when generally talking about cholesterol maybe Dr. Turco was talking about the LDL, while I guess Goljan was being specific in differentiating between LDL and cholesterol.

Is that the case?
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Old 03-23-2015
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Thank you spasemaster!

I am clear with goljan now. So total cholesterol - no fasting, LDL cholesterol-fasting because chylomicrons interfere.

I agree, that maybe Dr. Turco meant lipid profile and measuring LDL cholesterol specifically while saying that fasting is necessary.
I watched the video again. He is showing bell-shaped curve for 'transient hypercholesterolemia' 2-7h ofter eating and than adds that the curve is same for triglycerides, I guess it would be better to use postprandial transient hyperlipidemia and not hypercholoesterolemia because cholesterol is very little in chylomicrones so high chylomicrone level after eating can't make cholesterol level high and can't cause significant 'transient hypercholesterolemia'. Am I right? That's why it doesn't require fasting to measure total cholesterol, right?
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Yup, that's how I see it
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