Work-related insomnia affects one in five workers, which paves the way for mental health struggles, a new survey has revealed.

One-in-five workers experience a mental health condition, with 45 per cent of them facing stigma in the workplace, according to a July survey of 5047 Australian workers.

The figures, released on Tuesday by mental health organisation SuperFriend, show younger workers, aged between 18 and 24, experienced the most stigma at work over their mental health conditions.

"People at work don't disclose when there isn't a culture of trust, or a good working relationship with their manager," SuperFriend CEO Margo Lydon says.

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Those struggling with work-related insomnia, one of the initial signs of mental illness, said work affected the hours they slept, and quality, with difficulties switching off their mobiles and waking up in the night going over to-do-lists, Ms Lydon said.

The annual report, Indicators of a Thriving Workplace Survey, revealed an increase in the proportion of workers with mental health issues, up from one-in-six in last year's survey.

The increase could mean more people with mental health conditions have found employment, but Ms Lydon said the more likely reason was more people were experiencing work-related stress, especially as questions around job security become more common.

AAP

Poor job design, including reduced autonomy and unreasonable workload, was another big barrier to establishing a healthy environment, Ms Lydon said.

"If they're not well designed, it doesn't matter who you put into that role, they may typically experience poor mental health," she told AAP.

In Australia, poor mental health has been estimated to cost the economy more than $12 billion each year, including over $200 million worth of worker's compensation claims, according to the Black Dog Institute.

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Ms Lydon said the majority of survey respondents (64 per cent) believed investment in workplace mental health and wellbeing would improve productivity, with 55 per cent of Australian workers saying it would also reduce sickness and absences.

One survey respondent said: "I think most employers are just not equipped or educated to deal with mental health issues and therefore most of the time would not even think to relate a productivity issue or absenteeism issue to a potential mental health issue."

Organisations need to understand their current state, as the first step to change, Ms Lydon said.

Improvements don't need to be costly, as workplaces can heavily promote any existing initiatives such as employee assistance programs and ask employees directly for ideas to improve culture.

More information: Beyond Blue and Black Dog Institute.

Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14, Suicide Call Back Service on 1300 659 467 and Kids Helpline on 1800 55 1800 (for young people aged 5 to 25).