HDL Cholesterol
High-density lipoprotein – the 'good' cholesterol
Also known as
Definition
HDL cholesterol facilitates reverse cholesterol transport by shuttling excess cholesterol from arterial walls back to the liver. High HDL levels are considered cardioprotective, although HDL function (cholesterol efflux capacity) matters more than the measured value alone. Regular physical activity and smoking cessation sustainably raise HDL levels.
| Parameter | Value |
|---|---|
| Unit | mg/dl (mmol/l) |
| Reference Range | Women: > 50 mg/dl | Men: > 40 mg/dl |
Agree on your personal target range with your doctor.
Conversion: 1 mg/dl × 0.02586 = mmol/l. US labs report mg/dl; international studies also use mmol/l.
↓ What a low value means
Low HDL (< 40 mg/dl men, < 50 mg/dl women) is an independent risk factor for heart attack and stroke. Causes: physical inactivity, smoking, obesity, hypertriglyceridemia (HDL and triglycerides move inversely), type 2 diabetes, metabolic syndrome, genetic hypoalphalipoproteinemia. Low HDL combined with high triglycerides and high ApoB is particularly atherogenic.
↑ What a high value means
Very high HDL is not necessarily protective — clinical studies show U-shaped curves. Extreme values may indicate rare genetic disorders (CETP deficiency, cholestasis), dysfunctional HDL, or measurement error. Moderately high HDL from exercise is considered cardioprotective.
✓ What can influence this value
HDL cholesterol is influenced by physical activity (aerobic training can raise the value), smoking (can lower the value), body weight, diet, and alcohol consumption. Moderate alcohol consumption can raise HDL but is not regarded as a measure from a health perspective. Omega-3 fatty acids can raise the value moderately, and trans fats can lower it. Genetic factors, sex, diabetes, and certain medications also act on the value. The assessment is made by the treating doctor.
When to test
In the lipid panel always with total cholesterol, LDL, and triglycerides. For an accurate triglyceride measurement, labs usually ask for a fasting period; HDL itself is not fasting-dependent. The lipid panel is measured at checkups and with cardiovascular risk factors. How often it is measured is decided by your doctor.
Frequently asked questions
Can HDL be too high? +
Yes. With very high HDL, large studies show no additional protection — some even show mildly elevated mortality. HDL function (efflux capacity) is more important than the raw value. Very high values from exercise are, however, considered unproblematic.
How does exercise affect HDL? +
In studies, regular aerobic training is associated with a moderate rise in HDL over several months. Strength training has a smaller but measurable effect.
What is the relationship between HDL and triglycerides? +
HDL and triglycerides are metabolically linked via CETP (cholesteryl ester transfer protein). High triglycerides lower HDL (triglyceride-HDL exchange). Low HDL + high triglycerides is a central feature of metabolic syndrome.
HDL Cholesterol
Sources
Last updated: May 28, 2026
This information is for orientation only and does not replace medical advice. Reference ranges can vary by laboratory, method and country.