What is the Friedewald equation?

Friedewald (1972) estimates LDL as TC − HDL − TG/5. It is reliable when triglycerides are below 400 mg/dL; above that, direct LDL measurement is recommended.

Why is non-HDL cholesterol important?

Non-HDL cholesterol (TC − HDL) captures every atherogenic lipoprotein (LDL, VLDL, IDL, Lp(a)). The 2018 AHA/ACC guideline highlights it as a key secondary target.

What is a good total cholesterol level?

Generally, total cholesterol below 200 mg/dL is considered desirable, but treatment decisions are driven primarily by LDL, non-HDL, and overall cardiovascular risk.

Should I use direct LDL or Friedewald?

Direct LDL is preferred when triglycerides exceed 400 mg/dL or in non-fasting samples. Otherwise Friedewald is accurate enough for routine assessment.