Total cholesterol is the sum of the cholesterol carried in all lipoprotein particles in the blood — chiefly LDL and HDL, with a smaller contribution from triglyceride-rich particles. Cholesterol itself is a structural component of cell membranes and a precursor of bile acids, steroid hormones and vitamin D. The figure is a coarse summary of lipid transport and of long-term cardiovascular risk.
No readings for this marker yet.
Raised values most often reflect a diet-and-genetics combination, and markedly high results raise the question of familial hypercholesterolaemia; hypothyroidism, cholestasis, nephrotic syndrome, poorly controlled diabetes and some medicines also raise it. Low values are less often a concern in themselves but can accompany hyperthyroidism, liver disease, malabsorption or severe illness. Because the total mixes atherogenic and protective fractions, a normal total can hide a low HDL or a high LDL, and a raised one is not by itself a diagnosis. A doctor judges it in the context of overall cardiovascular risk.
Values drift with recent illness, pregnancy, weight change and thyroid status, and fall transiently in the weeks after an acute infection or myocardial infarction; posture and prolonged tourniquet time can nudge them upward. Statins such as atorvastatin and rosuvastatin lower it, while some antipsychotics and antidepressants raise it. Total cholesterol is read with LDL, HDL, triglycerides and non-HDL cholesterol, with apolipoprotein B or lipoprotein(a) added when risk assessment needs more resolution.
Reference ranges are general adult values and depend on lab, assay, age and sex. For orientation, not diagnosis — discuss results with your doctor.