HDL vs LDL cholesterol: what's the difference?

Cholesterol travels in your blood on two main carriers. LDL is the “bad” one that clogs arteries; HDL is the “good” one that clears it away. Here’s the simple version — and why the balance matters most.
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LDL — the “bad” cholesterol

Low-density lipoprotein (LDL) carries cholesterol to your tissues. When there’s too much, it builds up in artery walls as plaque, narrowing them and raising the risk of heart attack and stroke. For LDL, lower is better.

HDL — the “good” cholesterol

High-density lipoprotein (HDL) ferries cholesterol away from the arteries back to the liver, where it’s removed. Higher HDL is generally protective — which is why, for HDL, higher is better.

Why the balance matters

It’s not just each number in isolation — the balance between them predicts risk well. That’s what your total-to-HDL ratio (total cholesterol ÷ HDL) captures. Under about 3.5 is often considered optimal; 5 or above is high. Non-HDL cholesterol (total minus HDL) is another strong, fasting-free measure of all the harmful cholesterol combined.

How to shift the balance

Unsaturated fats, soluble fibre, activity and losing excess weight lower LDL and can raise HDL. Stopping smoking lifts HDL; cutting refined carbs and alcohol lowers triglycerides. Medication (like statins) is added when needed.

Frequently asked questions

Sources

Educational use only. This article provides general information and is not a medical diagnosis or a substitute for professional advice. Always talk to a qualified healthcare professional about your health.

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