Blood cholesterol

Cholesterol is a waxy, fat-like substance necessary to make hormones and vitamin D, and to help you digest food. Your body produces cholesterol, and it’s also in some foods.  

The human body uses cholesterol to build cells, but too much can put you at risk of heart disease.  

Types of cholesterol

1. Low-density lipoprotein (LDL) – the ‘bad’ cholesterol  
2. High-density lipoprotein (HDL) – the ‘good’ cholesterol. 
   

Low-density lipoprotein  

High-density lipoprotein 

Cholesterol and triglycerides 

What are the signs and symptoms of high cholesterol? 

High cholesterol generally doesn’t have obvious symptoms, but it can increase the risk of serious health conditions if left untreated. That’s why it’s important to get a blood test and regular check-ups. 

If you are 45 or older (30 or older, if you are Aboriginal or Torres Strait Islander), see your doctor for a cholesterol test as part of a Heart Health Check. If you have a family history of high cholesterol, speak to your GP about your heart disease risk.

Why is high cholesterol bad for you? 

If you have high cholesterol, you can develop fatty deposits in your blood vessels. This makes it difficult for blood to flow through the arteries. If these deposits break apart, they can form a clot that leads to a heart attack or stroke. 

Total cholesterol is a measure that includes good and bad cholesterol. It’s not always the best measure of your risk of heart disease on its own. The best way to understand these levels and your risk for heart disease is to see your GP for a Heart Health Check.

What causes high cholesterol?

There is no single cause of high cholesterol, but there are some controllable risk factors (e.g. smoking) and non-controllable risk factors (e.g. age).

Risk factors for high cholesterol include:

• Age
• ​Smoking
• Lack of physical activity
• Overweight or obesity
• Family history
• ​Unhealthy diet. 

No matter what the cause, improving your lifestyle, including your diet, can help reduce your risk of heart disease. 

How is cholesterol measured?

Cholesterol is measured with a blood test called a lipid panel or lipid profile. A cholesterol test usually involves having your blood drawn from a vein in your arm. The test can help determine your risk of atherosclerosis, which is a build-up of plaque that narrows or blocks arteries.

How to interpret your cholesterol results 

Guidelines for target cholesterol levels vary based on factors such as age and family history, so ask your doctor what levels are right for you.

A full blood-cholesterol test usually checks: 

• Total cholesterol
• LDL cholesterol
• HDL cholesterol
• Triglycerides
• ​Non-HDL cholesterol.

How can you lower high cholesterol? 

There are several ways to help lower high cholesterol, like staying active and eating or avoiding certain foods.