Of course you're right; I'm using colloquial shorthand. I'm referring to apolipoproteins bound to lipids and cholesterol (at which point we can call them lipoproteins). What I really am talking about is VLDL-cholesterol, LDL-cholesterol, HDL-cholesterol, and triglycerides.

awolf's challenge is particularly relevant and on-point because extremely low levels of LDL-cholesterol from birth (hypobetalipoproteinemia or abetalipoproteinemia) is associated with neurological deficits. When caused by defective APOB, it is also associated with non-alcoholic fatty liver disease.