Lipid Profile (Total/HDL/LDL/TG) Classifier

Lipid panel: cholesterol fractions and triglycerides

A standard lipid profile gives you four numbers: total cholesterol (TC), HDL-c, LDL-c, and triglycerides (TG). The LDL is either measured directly or worked out with Friedewald, LDL = TC − HDL − TG/5, which only holds up when TG < 400 mg/dL. Reference ranges here follow the Brazilian Society of Cardiology Dyslipidemia Guideline (V Diretriz, 2017, updated 2019). TC is considered desirable at <190 mg/dL, borderline from 190–239, and high at ≥240. For triglycerides, the cutoff is <150 mg/dL after a 12-hour fast, or <175 without fasting.

How low your LDL should go depends on your cardiovascular risk. Someone at low risk aims for an optimal <100 mg/dL; high risk pushes the target to <70, and very high risk (after a cardiac event, or diabetes with target-organ damage) to <50. HDL works the other way, since it's protective: you want ≥40 mg/dL in men and ≥50 in women. A quick atherogenic index is the TC/HDL ratio, which should stay under 4.5 in women and 5.0 in men. As for non-HDL cholesterol (TC − HDL), keep it 30 mg/dL above whatever your LDL target is.

Applications

It comes up in primary and secondary prevention of atherosclerotic cardiovascular disease, when titrating statins, ezetimibe, PCSK9 inhibitors or fibrates, and when tracking how someone responds to diet, weight loss or physical activity. It also helps screen for familial hypercholesterolemia, suggested by LDL >190 mg/dL alongside a positive family history. You'll get the most out of it paired with a global risk score such as Framingham, ASCVD or ER-Brazil.

FAQ

Do I still need to fast? Not necessarily. Current guidelines accept non-fasting samples for TC, HDL and LDL. A 12h fast is still the better option when TG > 440 mg/dL or when LDL is being estimated by Friedewald.

What is non-HDL cholesterol? It adds up every atherogenic particle (LDL + VLDL + IDL + Lp(a)). You calculate it as TC − HDL, and it tends to predict events better than LDL on its own, particularly in people with diabetes or hypertriglyceridemia.

Does this tool replace a doctor? No. Think of it as an educational reference built on SBC cutoffs. It won't stand in for a clinical evaluation or treatment from a qualified professional.