Depression is now the leading cause of ill health and disability worldwide, according to the World Health Organisation.
Rates of depression have risen by more than 18 per cent since 2005, with 300 million people estimated to suffer from the condition.
Despite this, a lack of support and stigma means many people aren't getting the treatment they need to live healthy and productive lives, WHO director-general Dr Margaret Chan said from the UN agency's Geneva headquarters.
"These new figures are a wake-up call for all countries to re-think their approaches to mental health and to treat it with the urgency it deserves," she said in a statement.
Depression is a common mental illness characterised by persistent sadness and a loss of interest and lack of ability in everyday activities and work.
According to the latest Australian Bureau of Statistic figures, every year in Australia around six per cent of all adults will be affected by a depressive illness
Dr Stephen Carbone, Policy, research and evaluation leader at beyondblue says depression can occur at any age and is a health condition just like diabetes that needs to be effectively treated.
"Yes it affects you differently in that it's affecting your thoughts, behaviour and feelings not just your physiology but at the end of the day we shouldn't be judging or criticising people or treating people differently just because of a particular health condition they have," Dr Carbone told AAP.
People must not be "fooled" into thinking depression is any less of a concern than cancer or heart disease, Dr Carbone said.
"Even though it might not rank as high as cancer or cardiovascular disease in deaths it certainly ranks higher in terms of the disabling effects of the condition on your day-to-day life and quality of life," he said.
To tackle the stigma and misconceptions about the mental illness WHO is running a campaign called 'Depression: Let's Talk'.
"For someone living with depression, talking to a person they trust is often the first step towards treatment and recovery," said Shekhar Saxena, director of the WHO's mental health department.
Just exposing sufferers to stories about how depression has affected 'every day people' across various spectrums of life helps, says Dr Carbone.
"The more we hear how common this condition is the more we realise 'it could happen to me' there's nothing to be scared about and hopefully that will encourage people to step forward and seek information and assistance for their depression."