Cholesterol is a type of fat in your blood. Most cholesterol is made by your body, but eating fatty foods can lead to high cholesterol levels. Your arteries may clog up with the fatty cholesterol, which increases your risk of having a heart attack or stroke.
Key points about high cholesterol
You can't tell or feel if you have high cholesterol.
Talk to your doctor or nurse about your overall heart risk and what you can do to keep your heart and cholesterol numbers well controlled.
With treatment and lifestyle changes, the risks of complications from high cholesterol are much less.
If you need medication, take it every day as prescribed and ask questions if you don't understand anything.
What is high cholesterol?
High cholesterol is when there's too much bad cholesterol (LDL) and/or not enough good cholesterol (HDL) in your blood. This picture shows what it looks like if you have low cholesterol, normal cholesterol and bad cholesterol levels.
Image source: Heart Foundation, NZ
How do I know if I have high cholesterol?
High cholesterol usually does not have symptoms. The only way to find out if your cholesterol is high is to have a blood test called a lipid profile. This measures the amount of cholesterol and triglycerides in your blood. Read more about cholesterol testing.
What is the treatment for high cholesterol?
Your doctor will assess your risk of heart attack or stroke based on your lipid profile results and other risk factors such as age, sex, blood pressure, smoking and diabetes. Your doctor may give you medication such as statins to lower cholesterol and reduce your risk of having a heart attack or stroke.
What can I do to lower my cholesterol?
You may be able to reduce your cholesterol by making changes to your lifestyle such as:
eating healthy foods, including lots of fruit and vegetables, low or reduced fat milk, lean meat, nuts and seeds
avoiding takeaways and deep fried foods, cakes, biscuits, pastries and chips
reducing red meat, cheese and butter
staying at a healthy weight
exercising regularly – being active for at least 30 minutes a day most days of the week
not drinking too much alcohol
eating healthy fats.
Image source: BPAC, NZ
How can I work out if I am at risk of heart disease?
A heart risk assessment will help you find out your risk of heart disease by building a picture of your risk based on factors such as your age, sex, ethnicity, cholesterol levels, smoking history, blood pressure, family history and other health conditions.
Different people need a heart risk assessment at different ages. Find out more aboutheart risk assessment.
My Heart Check
As well as seeing your GP for a heart risk assessment, you can check your heart health withMy Heart Check. It's a free online heart health checkdesigned for Kiwis by the Heart Foundation.
It can estimate your heart age compared to your actual age, as well as giving you an estimate of your risk of having a heart attack or stroke in the next 5 years. Note that this free online tool works best for people aged 30–75. You can still use it if you are older or younger, but your result may be less accurate.
Credits: Health Navigator Editorial Team. Reviewed By: Andy McLachlan, Counties Manukau DHB
Last reviewed: 18 Apr 2017
What is a cholesterol test for?
The only way to find out if your cholesterol is high is to have a blood test called a lipid profile. This measures the amount of cholesterol and triglycerides in your blood.
Knowing your cholesterol levels helps your doctor to assess your overall heart health and see if any lifestyle changes or other treatment is needed.
How is a cholesterol test carried out?
Some cholesterol tests are done using a finger-prick blood sample, but more detailed testing means a blood sample needs to be collected from a vein in your arm.
You may need to fast (go without food and drink apart from water) for about 8 hours before taking the test. If so, your local community diagnostic laboratory or doctor will tell you in advance. You can have your test done first thing in the morning to make fasting less inconvenient. You should still be allowed to drink water and take your normal medications – do not stop taking these unless your doctor tells you to.
If you are taking blood-thinning medications (eg, aspirin or warfarin), or have bleeding or clotting problems, tell the nurse or laboratory staff about this before the blood sample is taken.
When and where do I have a cholesterol test?
Normally, your doctor will ask you to have the cholesterol test at the nearest community diagnostic laboratory, or the practice nurse may be able to take the blood sample.
If you have had recent surgery, a heart attack or been unwell (eg, influenza), it is better to wait at least 6 weeks before having the test done, for a more accurate result.
Pregnant women should wait at least 6 weeks after your baby is born to have cholesterol measured, as cholesterol is higher during pregnancy.
What levels are measured?
The cholesterol blood test result will give levels of:
These make up your blood lipid profile. Lipids are just another name for the fatty substances in your body and bloodstream.
New Zealand health guidelines for acceptable blood cholesterol levels are are follows:
HDL cholesterol – greater than 1.0 mmol/L
LDL cholesterol – less than 2.0 mmol/L
Triglycerides – less than 1.7 mmol/L
Total cholesterol – less than 4.0 mmol/L
TC/HDL ratio – less than 4.0.
What do my cholesterol test results mean?
Your doctor will tell you the results of the blood tests. The results are not interpreted on their own and are not used to diagnose a disease. Instead, they provide information on your overall health and your risk of heart attack and stroke. Sometimes high cholesterol levels can be an early warning to make lifestyle changes to lower your risk of cardiovascular disease.
Your doctor will use other cardiovascular disease risk factors such as your age, sex, blood pressure and whether you smoke or have diabetes when deciding whether treatment is needed.
Information for healthcare providers on high cholesterol
The content on this page will be of most use to clinicians, such as nurses, doctors, pharmacists, specialists and other healthcare providers.