HDL Cholesterol: What Your Number Means

HDL cholesterol is the "good cholesterol" on your lipid panel. A higher HDL has long been linked to lower heart risk, but drugs that raise HDL haven't prevented heart attacks, so clinicians read HDL as a marker of your metabolic health and aim treatment at other numbers. This guide explains what your HDL level means and what to do with it.

What is HDL cholesterol?

HDL (high-density lipoprotein) is the particle that carries cholesterol away from artery walls and back to the liver, a process called reverse cholesterol transport. That job earned it the "good cholesterol" nickname. Large observational studies also consistently link higher HDL to lower cardiovascular risk.

Does raising HDL lower heart risk?

Not with the drugs tested so far. Several drug classes were built to raise HDL on the reasonable idea that if low HDL predicts risk, raising it should cut risk, and the large trials didn't bear that out:

• Niacin reliably raises HDL. Added to a statin, it did not reduce cardiovascular events in AIM-HIGH, which was stopped early for lack of benefit, or in HPS2-THRIVE, which also found more serious side effects.
• CETP inhibitors raise HDL a lot. Torcetrapib increased deaths and cardiac events in the ILLUMINATE trial. Anacetrapib did lower events modestly in the REVEAL trial, but it also lowered non-HDL cholesterol, which is the likelier reason. A newer CETP inhibitor, obicetrapib, is being studied mainly for lowering LDL cholesterol (LDL-C) (see emerging therapies).

HDL probably reflects good metabolic health, and a drug that pushes the number up doesn't create that health. So current treatment focuses on lowering LDL and ApoB, which has repeatedly been shown to reduce heart attacks and strokes.

What is a good HDL level?

A good HDL level is above 40 mg/dL for men and above 50 mg/dL for women, with 60 or higher traditionally counted as protective. Very high levels aren't extra protective.

• Low, and worth looking into: below 40 mg/dL in men, below 50 mg/dL in women
• Traditionally considered protective: 60 mg/dL or higher
• Extremely high (roughly 97 mg/dL and up in men, 116 and up in women): In two large Danish population studies, these levels were linked to higher all-cause death rates, a U-shaped curve.

How do you improve your HDL?

Habits that improve your overall metabolic health raise HDL modestly and, more importantly, improve what HDL reflects:

• Regular aerobic exercise
• Quitting smoking, which lowers HDL directly
• Losing excess weight, particularly visceral fat
• Cutting back on refined carbohydrates and added sugar, which also lowers triglycerides

Skip chasing an HDL number, because these habits improve the overall metabolic state that a healthy HDL reflects.

Summary

A low HDL is worth noticing, mainly because of what it often travels with: high triglycerides, insulin resistance, excess weight. On its own, low HDL doesn't call for medication. Keep your focus on the numbers that predict risk and respond to treatment: LDL-C and ApoB.

At Preval Health, we review HDL as part of the full lipid picture and our protocols base treatment decisions on LDL-C, ApoB, and Lp(a), the markers with a proven, causal link to heart attacks and strokes. Our advanced lipid testing page explains which labs we use and why, and our guide to the advanced lipid panel covers what HDL particle tests do and don't add.