Health & Fitness · LDL 与 HDL（低/高密度脂蛋白） · Updated 2026-10-25
What Is LDL and HDL Cholesterol?
Definition
The atherosclerosis driver on a lipid panel is LDL-C, which deposits cholesterol into the vessel wall as plaque. Targets vary: healthy <3.4 mmol/L; with diabetes or smoking <2.6; established coronary or stroke <1.8, sometimes <1.4. HDL-C performs reverse transport (>1.0 mmol/L desirable), but drugs that raise HDL have shown no benefit — exercise and smoking cessation are the real levers. Triglycerides swing with recent meals, so fast before testing.
Formula
LDL-C targets: healthy <3.4; high-risk <2.6; established ASCVD <1.8 mmol/L
Worked Example
A 45-year-old man with LDL 3.8 and no other risk factors: 3 months of diet (zero trans fat + oats/nuts/fish) and exercise; recheck at 3.2 hits target. With diabetes, start a statin immediately.
Common Misconception
"Total cholesterol normal, all good" — LDL fraction matters even when the total looks fine; read the panel by LDL tier. "Higher HDL is always better" — above 2.6 mmol/L shows no added protection and may associate with risk in some groups. And eggs are overblown: for most people saturated and trans fats move LDL far more than dietary cholesterol.
Matching Calculators
Related Terms
Keep Exploring
Browse the full glossary, or head back to the homepage for 1,435 free online calculators.
Back to glossary