Nov 9Liked by Richard Sprague

Labs performing tests typically provide you with reference ranges for their tests. Labcorp and Quest for example have the same test method and reference ranges for vitamin D, but use different test methods with slightly different reference ranges for testosterone. I'm guessing SiPhox still needs to establish the reference ranges for whatever it is they are doing.

Like blood sugar and blood pressure, cholesterol (and related markers) changes throughout the day, so it would be useful to both know your "fasting" levels as well as having more continuous data.

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Total cholesterol is an ambiguous test to begin with, as the highest total mortality rate for both men and women is seen below 160 mg/dl. I think it's crazy to flag 200 as high as many labs do, as that is actually where you want to be. We should really be focusing on HDL-C and triglycerides, and both should be taken fasting.

I use fasting triglycerides divided by fasting HDL as a rough estimate of LDL particle size. That ratio ideally should be below 2.0. Lower ratios indicate larger diameter LDL, which is thought to be more benign. I know people with ratios below 1.0, even below 0.5, which indicates to me a relatively low risk of ischemic stroke or heart attack. However, such a person could still have high BP and be at considerable risk for other serious health conditions, such as kidney disease or the type of stroke associated with bursting blood vessels.

An example of a poor ratio would be fasting triglycerides of 250 and fasting HDL of 50, a ratio of 5.0. I would be concerned about the condition of the coronary arteries of such a person and would suspect possible atherosclerotic lesions, with considerably increased cardiovascular risk.

I've had very consistent results with the provider I use and have no particular reason to doubt my lab results, but there is no doubt variability among labs.

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