Causes of depression

We don’t know exactly what causes depression. However, we do know there are a number of things linked to its development.

Depression usually develops because of a combination of life events, personal factors and changes in the brain. It doesn’t usually develop because of one issue or event.

Illustration of a woman feeling overwhelmed with a lot on her mind

Family history

Depression can run in families and some people will be at an increased genetic risk.

Having a parent or close relative with depression doesn’t mean you’ll automatically have the same experience. Life circumstances and other personal factors are still likely to have an important influence.


Some people may be more at risk of depression because of their personality. Risk factors include:

  • tendency to worry a lot

  • low self-esteem

  • perfectionism

  • sensitivity to personal criticism

  • self-criticism and negativity.

Serious medical illness

The stress and worry of coping with a serious illness can lead to depression, especially if it’s long-term or you’re dealing with chronic pain.

Drug and alcohol use

Drug and alcohol use can lead to depression. Many people with depression also have drug and alcohol problems.

Over 500,000 Australians will experience depression and a substance use disorder at the same time, at some point in their lives.

Life events

Research suggests that continuing difficulties are more likely to cause depression than recent life stresses. This can include:

  • long-term unemployment

  • living in an abusive or uncaring relationship

  • long-term isolation or loneliness

  • prolonged work stress.

Recent events (such as losing your job) or a combination of events can ‘trigger' depression if you’re already at risk because of previous bad experiences or personal factors.

Changes in the brain

A lot of research has been done into this complex area, but there’s still a lot we don’t know.

Depression isn’t simply the result of a ‘chemical imbalance’, like having too much or not enough of a particular brain chemical.

The way your brain regulates your moods can be affected by:

  • genetic vulnerability

  • severe life stressors

  • some medications, drugs and alcohol

  • medical conditions.

Most modern antidepressants affect your brain’s chemical transmitters (serotonin and noradrenaline), which relay messages between brain cells. This is thought to be how medications work for more severe depression.

Psychological treatment can also help you to regulate your moods.

Effective treatment can stimulate the growth of new nerve cells in circuits that regulate your mood. This may help you recover from severe depression.

Learn more: Treatments for depression.

Do I have depression?

It can be hard to know whether you’re feeling depressed or have depression.

Our anonymous Anxiety and Depression Test (K10) can help you understand whether your anxious feelings are the kind of worries that will go away on their own, or whether it’s time to get more support to help you feel better.

It’s an evidence-based test that asks 10 questions about how you've been feeling over the past 4 weeks. Australian doctors and mental health professionals use this test, known as the K10. They sometimes ask you to take the K10 and talk about it with you.

Start the K10 test

Finding mental health support

Your GP can be a good place to start the conversation about your mental health.  

We can also help you find other support that’s right for you. This could include talking to our counsellors or helping you find a mental health professional near you. 

Get mental health support

Connect with our online peer support community

Anonymously read, share and learn from people who are also living with depression.

The Beyond Blue Forums is a welcoming peer support community.

Visit the Beyond Blue Forum depression discussions

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