Cholesterol Test Results Explained: LDL, HDL, Triglycerides and Non-HDL

Your cholesterol result is more than one number. The balance between “bad” and “good” cholesterol, and your overall heart risk, matter far more than total cholesterol alone.

Imagine getting a result that says “total cholesterol 5.8”. Your friend’s is 6.2 and her healthcare provider isn’t worried. Yours wants to talk about statins. Why the difference?

What a lipid profile includes

• Total cholesterol
• LDL (“bad”) cholesterol: builds up in artery walls
• HDL (“good”) cholesterol: helps remove cholesterol
• Non-HDL cholesterol: total minus HDL, a useful marker of risk
• Triglycerides: a type of fat in the blood

General healthy guides for adults

• Total cholesterol: below 5 mmol/L (below 200 mg/dL)
• LDL: below 3 mmol/L (below 100 mg/dL is often described as optimal in the US)
• HDL: above 1.0 mmol/L for men and above 1.2 mmol/L for women (above 40 and 50 mg/dL)
• Triglycerides: below 1.7 mmol/L fasting (below 150 mg/dL)
• Targets are lower for people with heart disease or diabetes

Why your overall risk matters

Doctors look at cholesterol alongside age, blood pressure, smoking, diabetes, family history and other factors, often using a risk calculator. Two people with the same cholesterol can have very different risk.

Do you need to fast?

Many guidelines say fasting is not usually needed. Triglycerides can be higher after eating, so your clinician may ask you to fast in some cases.

Lab ranges vary

Reference ranges differ between laboratories and countries, and some use different units. Always compare your result with the range printed on your report and discuss it with your healthcare provider.

Why LDL cholesterol matters most

LDL particles carry cholesterol into the walls of arteries. Over years, this builds up into fatty plaques that narrow the arteries and can rupture, triggering a heart attack or stroke. The evidence that lowering LDL reduces heart attacks and strokes is among the strongest in medicine.

This is why treatment targets usually focus on LDL or non-HDL cholesterol rather than total cholesterol. For people who have already had a heart attack or stroke, many guidelines recommend lowering LDL much further than for the general population, often below 1.8 mmol/L (70 mg/dL) or even lower.

HDL: is “good” cholesterol always good?

Higher HDL is generally linked with lower heart risk, and low HDL is a warning sign. However, medicines that raise HDL have not been shown to prevent heart attacks, and very high HDL is not necessarily protective. Healthcare providers mainly use HDL as part of overall risk calculations rather than a target in its own right.

Triglycerides

Triglycerides are fats that rise after meals and are affected by alcohol, sugar, refined carbohydrates, excess weight and poorly controlled diabetes. Moderately high triglycerides add to heart risk.

Very high triglycerides, usually above 10 mmol/L (about 880 mg/dL), can cause acute pancreatitis, a painful and potentially serious condition. People with very high levels need prompt assessment and treatment.

How heart risk is calculated

Most countries use a risk calculator that estimates the chance of a heart attack or stroke over the next 10 years. Examples include QRISK in the UK, the Pooled Cohort Equations and PREVENT in the US, and SCORE2 in Europe. These combine age, sex, cholesterol, blood pressure, smoking, diabetes, kidney disease and other factors.

Your result helps decide whether lifestyle changes alone are enough or whether a cholesterol-lowering medicine such as a statin is recommended. Ask your healthcare provider for your score and what would lower it.

Lifestyle changes that help

• Replace saturated fats (fatty meat, butter, palm and coconut oil) with unsaturated fats such as olive, sunflower or rapeseed oil, nuts and oily fish
• Eat more fibre from oats, beans, lentils, fruit and vegetables
• Limit processed meats, sugary foods and refined carbohydrates
• Stay active: aim for at least 150 minutes of moderate activity a week
• Stop smoking, which also lowers HDL
• Keep alcohol within recommended limits, especially if triglycerides are high
• Lose weight gradually if you are overweight

Cholesterol-lowering medicines

Statins are the most widely used and best-studied cholesterol medicines. They lower LDL and reduce the risk of heart attacks and strokes. Most people take them without problems; muscle aches are the most commonly reported side effect, but studies suggest many of these aches are not actually caused by the statin.

Other medicines include ezetimibe, PCSK9 inhibitors and inclisiran, which may be used if statins are not enough or not tolerated. Never stop a prescribed medicine without discussing it with your healthcare provider.

Cholesterol in children and young adults

Familial hypercholesterolaemia is an inherited condition affecting around 1 in 250 people. It causes very high LDL from birth and early heart disease if untreated. If a parent or sibling has it, or had a heart attack at a young age, children and other relatives may be offered testing. Early treatment can greatly reduce future risk.

Lipoprotein(a): the inherited risk factor

Lipoprotein(a), often written Lp(a), is a type of cholesterol particle whose level is mostly set by your genes. High Lp(a) increases the risk of heart attack and stroke even when other cholesterol levels look normal. Many guidelines now suggest checking it at least once in adulthood, especially if you have a strong family history of early heart disease. Lifestyle changes have little effect on Lp(a), but knowing your level helps your healthcare provider judge your overall risk.

Before your cholesterol test

• Ask whether you need to fast; most people do not
• Avoid heavy drinking the day before, as it can raise triglycerides
• Tell your healthcare provider if you have recently been unwell, as illness can temporarily change results
• Bring a list of your medicines, including supplements

Questions to ask about your results

• What is my LDL or non-HDL cholesterol?
• What is my 10-year heart risk?
• Would a statin or other medicine benefit me?
• What lifestyle changes would make the biggest difference?
• When should I be tested again?

Frequently asked questions

What is familial hypercholesterolaemia?

An inherited condition causing very high LDL from a young age. Total cholesterol above about 7.5 mmol/L, or a family history of early heart disease, may prompt testing.

Can diet alone lower cholesterol?

Diet and exercise help, often by around 5 to 10%. Some people also need medicines.

How often should cholesterol be checked?

It depends on your age and risk. Many adults have it checked every few years; people on treatment are usually checked more often.

Can thin people have high cholesterol?

Yes. Genetics play a big role, so people of any size can have high cholesterol.

Do eggs raise cholesterol?

For most people, eggs in moderation have only a small effect on blood cholesterol. Saturated fat has a bigger effect.

But I feel healthy. Why treat a number?

High cholesterol causes no symptoms, but it increases the risk of heart attack and stroke over time.

Related: How to lower cholesterol · Normal lab values cheat sheet

Sources: NHS, Heart UK, National Institute for Health and Care Excellence (NG238), American Heart Association, US Centers for Disease Control and Prevention.