HDL Cholesterol
High-Density Lipoprotein
What this test measures
HDL is often called 'good' cholesterol. It helps remove bad cholesterol from your blood and takes it to your liver to be broken down. Higher HDL is better for your heart.
Understanding the numbers
Typical range: Men: above 1 mmol/L | Women: above 1.2 mmol/L
Higher is better. Levels above 1.5 mmol/L give extra protection.
- Low (extra risk): 0.4–1 mmol/L
- Acceptable: 1–1.5 mmol/L
- Protective: 1.5–2.3 mmol/L
- Very high — may be neutral: 2.3–3 mmol/L
Key numbers
- 1.0 mmol/L — Men — minimum desirable
- 1.2 mmol/L — Women — minimum desirable
- 1.5 mmol/L — Level considered protective
- 2.3 mmol/L — Very high — newer evidence suggests benefit may plateau
Minimum desirable thresholds are from NICE NG181 / lipid profile interpretation in UK primary care. 'Protective' levels are population-level estimates; recent studies suggest very high HDL (above about 2.3 mmol/L) does not give further benefit and may be genetic.
Ranges can vary slightly between laboratories — your report may show slightly different numbers. This page does not read or interpret your result; your GP looks at it alongside your history and other tests.
What a higher-than-normal result can mean
- This is usually a good thing
- High HDL helps protect your heart
- Regular exercise and healthy fats can raise HDL
Questions you could ask your GP
- What can I do to raise my HDL level naturally?
- How does my HDL affect my overall heart disease risk?
- Would increasing exercise help improve my HDL?
- Are there any medicines that can help raise HDL?
Example stories
These are made-up examples to show how results are talked about in real appointments. They are not real patients.
Runner, asked to check lipids
Rashmi is a keen runner and has never smoked. Her HDL was 2.0 mmol/L — comfortably in the protective range. Her total cholesterol was 5.4, but her LDL was only 2.9 and her QRISK was 3%.
What the GP said: “Your total cholesterol is slightly above 5 but most of that is good cholesterol. Your overall heart risk is very low — keep doing what you're doing.”
A slightly raised total cholesterol with a high HDL often looks worse on paper than it is. What matters is the overall picture — LDL, HDL, and your full risk profile.
Metabolic syndrome picture
Bhavesh had an HDL of 0.8 mmol/L, triglycerides of 3.2, a waist of 104 cm and a QRISK of 16%.
What the GP said: “Your good cholesterol is low and your triglycerides are high — this pattern often comes with central weight gain and raises heart risk. We should talk about weight, activity, and starting a statin.”
What happened next: Over nine months Bhavesh lost 7 kg, started weight training, and began a low-dose statin. His HDL rose to 1.1 and his triglycerides dropped to 1.6.
Low HDL is often part of a bigger metabolic picture — central weight, high triglycerides, high blood pressure, and insulin resistance. Exercise and weight loss raise HDL in a way that few medicines can.
Smoker, on statin
Sanjay's HDL was 1.1 mmol/L. He smoked 15 a day and his LDL on simvastatin was 2.6.
What the GP said: “Your HDL is in the acceptable range but stopping smoking is the single biggest thing that would raise it and cut your heart risk. Let's talk about stop-smoking services.”
What happened next: Sanjay used the NHS stop-smoking service with varenicline. A year smoke-free, his HDL was 1.4 and his blood pressure had also improved.
Smoking lowers HDL and raises heart risk more than almost any other single factor. Stopping is hard, but HDL typically rises within months of quitting.
Very high HDL on routine check
Priti's HDL was 2.6 mmol/L. She had always had high HDL, and so had her mother.
What the GP said: “This is probably just your natural level — it often runs in families. We used to think higher was always better, but very high HDL doesn't seem to add protection and isn't a problem. No action needed.”
Very high HDL (above about 2.3 mmol/L) is usually genetic and doesn't need investigating. The old 'higher is always better' message has softened — the benefit appears to plateau.
Before you act on anything here
This page is general information, written to help you understand — it is not personal medical advice and it cannot tell you what is right for you. Talk to your own GP, pharmacist or nurse about your own health.
- Need help now but it's not an emergency? Call NHS 111 or use 111.nhs.uk.
- Emergency? Call 999 or go to A&E.