Your doctor has asked for a lipid profile, or your report lists total cholesterol, LDL, HDL and triglycerides and you are unsure what they mean. Reports may give the lipid profile normal range in mg/dL or in mmol/L, and each line tells your doctor something different about heart risk.
What a lipid profile test measures
A lipid profile is a blood test that measures the cholesterol and triglycerides (a type of fat) in your blood. Lab menus may also list it as a cholesterol test or lipid panel.
Cholesterol is a waxy, fat-like substance found in your blood and in every cell. Your body needs some of it to make hormones and vitamin D, and to help digest food. Your liver makes all the cholesterol you need. More comes from animal foods such as meat, egg yolks, poultry and dairy products, and foods high in fat can raise the level in your blood.
The main results on the report are:
- Total cholesterol: the total amount in your blood, which includes LDL and HDL
- LDL cholesterol, often called bad cholesterol: the main source of blockages in the arteries
- HDL cholesterol, often called good cholesterol: helps clear LDL from the blood
- Triglycerides: a type of fat in the blood; high levels may raise the risk of heart disease, especially in women
Other values you may see on the report
Some reports also show non-HDL cholesterol. This is simply your total cholesterol minus your HDL.
You may also see VLDL (very low-density lipoprotein). Like LDL, it adds to the build-up of plaque in the arteries, but it mainly carries triglycerides. VLDL is hard to measure, so routine tests usually leave it out, and when it is reported the lab has normally estimated it from your triglyceride level.
Why cholesterol is linked to heart disease
Too much LDL in the blood raises the risk of coronary artery disease and other heart disease. High LDL can cause a sticky substance called plaque to build up inside the arteries, a process called atherosclerosis. Over time, plaque can narrow an artery or block it completely.
A blocked artery to the heart can cause a heart attack. A blockage in the blood supply to the brain can cause a stroke, and blocked arteries in the arms or legs cause peripheral artery disease. A higher HDL level, on the other hand, may help lower the risk of heart attack or stroke.
Cholesterol is one part of the picture. The NHS describes how GPs in the UK combine cholesterol results with age, blood pressure and other health conditions to estimate the chance of a heart or circulation problem over the next 10 years. Ask your doctor how your own numbers fit with the rest of your health.
Who should get a cholesterol test and how often
MedlinePlus gives these general recommendations. Children should have a first test between ages 9 and 11, then every 5 years. Some children start as early as age 2 if high cholesterol, heart attack or stroke runs in the family.
Younger adults should be tested every 5 years. Men aged 45 to 65 and women aged 55 to 65 should be tested every 1 to 2 years, and people over 65 every year. You may need tests more often if you have a higher risk because of:
- A family history of heart disease
- High blood pressure
- Type 2 diabetes
- Smoking
- Excess weight or obesity
- Lack of physical activity
- A diet high in saturated fat
Lipid profile test fasting and preparation
You may be asked to fast, which means no eating or drinking, for 9 to 12 hours before the test. That is why the sample is often taken in the morning. Your doctor will tell you whether you need to fast and give any other instructions.
Advice is not the same everywhere. It does not make much difference to its guide levels whether you have eaten before the test. Follow the instruction on your slip or from the lab, and check whether other tests on the same slip need fasting.
The sample is taken from a vein in your arm and usually takes less than five minutes. You may have slight pain or a small bruise where the needle went in, which usually settles quickly.
Lipid profile normal range
Each lab prints its own reference range on the report, and ranges differ by lab, age and sex. Check the units first. Results are usually given in milligrams per decilitre (mg/dL) or in millimoles per litre (mmol/L), and the numbers look very different. A healthy level for you also depends on your age, family history, lifestyle and other heart risk factors, so ask your doctor to explain your report.
In mg/dL, healthy levels for adults aged 20 and over are listed below. For children and teenagers aged 19 or younger, healthy levels are lower: total cholesterol under 170 mg/dL, LDL under 110 mg/dL and HDL above 45 mg/dL.
In mmol/L, the guide for healthy adults is total cholesterol below 5, HDL above 1.0 for men or above 1.2 for women, and non-HDL below 4. Your levels may be higher or lower if you have been ill, are taking some medicines or have recently had a baby.
- Total cholesterol: less than 200 mg/dL
- Non-HDL cholesterol: less than 130 mg/dL
- LDL cholesterol: less than 100 mg/dL
- HDL cholesterol: 60 mg/dL or more is best; below 40 mg/dL in men or below 50 mg/dL in women is low
Ways to lower LDL cholesterol
Some risk factors, such as age and genes, cannot be changed. Others can. The steps below may help lower LDL and reduce heart risk.
Talk to your doctor before making any big change to your diet or exercise routine. A nutritionist can help you plan meals that cut down on saturated fat.
- Eat less food that is high in saturated fat and cholesterol
- Manage your weight
- Stay active, which may lower LDL and raise HDL
- Stop smoking, since smoking lowers HDL and raises LDL
- Reduce stress
- Avoid drinking too much alcohol
