Last updated: August 2020

Heart disease is the number one cause of death in Australia – in 2018, 11% of all deaths were as a result of heart disease.  Although there is not one single cause, an unhealthy diet can be one of the contributing risk factors for heart disease. Paying attention to what you eat and consuming a variety of healthy foods from the five food groups is one of the most important preventative measures you can take.

Characteristics of heart disease

Heart disease results from the narrowing of the arteries that supply the heart with blood through a process known as atherosclerosis. Fatty deposits (or plaque) gradually build up on the inside of the artery walls, narrowing the space in which blood can flow to heart. Atherosclerosis can start when you are young, so by the time you reach middle age, it can be quite advanced.

Plaque build-up can be considered as stable or unstable. If there is too much build-up of stable plaque, it narrows the arteries, causing pain and discomfort due to not enough blood reaching the heart – this is called angina and it needs to be treated.

Unstable plaque is inflamed and has a thin cap which is prone to developing a crack, allowing the blood to come in contact with the fatty contents of the plaque. The blood will clot to try to seal the gap but in doing so, the blood clot blocks the artery. This prevents the flow of blood to the heart, cuts off its oxygen supply and damages or kills the heart cells. This is a heart attack.

Risk factors for heart disease

There are many factors that can increase your risk of heart disease. Although some of these cannot be changed, the good news is that there are plenty of risk factors within your control. For example, by being physically active, ensuring you have good social support and not smoking, your risk of heart disease is reduced.

Risk factors that can’t be changed Risk factors within your control
Age Smoking status
Gender Diet
Ethnicity Cholesterol levels
Family history of heart disease Blood pressure
  Body weight
  Diabetes management
  Physical activity levels
  Depression and social isolation


Some risk factors are connected. For example, cholesterol levels and blood pressure can be affected by diet, as can your body weight and management of diabetes.

Therefore, one of the best things you can do to reduce your risk of heart disease is to have a healthy diet and maintain a healthy weight!

Dietary fats and cholesterol levels

Cholesterol is a fat crucial to many metabolic functions and is an essential part of all the body’s cell membranes. It is made by the body from the food we eat and is produced in the liver.

Blood lipids (fats) that contain cholesterol include low-density lipoprotein (LDL) and high-density lipoprotein (HDL). LDL (‘bad’) cholesterol can lead to plaque forming in the arteries while HDL (‘good’) cholesterol helps to remove cholesterol from the body and makes it harder for plaque to form in the arteries.

Saturated fats

Saturated fats (also known as ‘bad fats’) tend to increase LDL (‘bad’) cholesterol in the blood. Common sources of saturated fats include – animal products (butter, coconut oil, meat fat including lard and dripping, beef, lamb, chicken skin and palm oil), and processed foods like pastries and biscuits.

Full fat or reduced fat dairy?

Although full fat dairy foods (such as milk, cheese and yoghurt) contain saturated fat, it appears this type of fat has a neutral relationship with heart health. 

The Heart Foundation recommends unflavoured milk, yoghurt and cheese can be consumed by the general population but for people who need to lower their LDL cholesterol, reduced fat versions should be consumed instead.

Eggs

It was once thought cholesterol naturally found in eggs was bad for heart health. However, research suggests eggs have a neutral relationship with heart health – they neither increase nor decrease the risk of heart disease for the general population. 

People who need to lower their LDL cholesterol or those with type 2 diabetes, the Heart Foundation recommends a maximum of 7 eggs per week.