The mental health of many New Zealanders will hang in the balance during the coming months as the social repercussions of lockdown take hold.

The warning comes from across the board and on the same day Youthline said under 25-year-olds were struggling with the negative impacts of Covid-19 on their lives.

On Thursday the former prime minister's chief science adviser Sir Peter Gluckman told the Epidemic Response Committee many Kiwis have had their once certain futures ripped away from them.

There would be a lot of newly vulnerable people, Gluckman said, giving an example of a 55-year-old travel agent now out of work and without a future, who would join New Zealand's already disadvantaged.

The International Labour Organisation says the relationship between economic health and mental health is inextricably linked.

Internationally previous economic downturns and crises have been linked to growing mental health problems and spikes in suicide rates.

In the Economic Union every one per cent increase in unemployment was associated with a 0.8 per cent rise in suicides for people under 65 years.

Welfare agencies and foodbanks, often the frontline response to poverty, have reported record numbers of requests as the Covid-19 pain bites.

Gluckman said the fallout from lockdown would be an increase in fear, anxiety and frustrations.

The primary need now was to support the social services providing help and solutions to our communities and the focus had to be on how to mitigate the effects of the crisis, he said.

Mental Health Foundation chief executive Shaun Robinson said our biggest threat to mental wellbeing going forward was economic impact.

"Things like losing jobs, businesses failing and not being able to feed your family are going to have a huge impact and it's completely natural that people are going to become stressed in those situations."

But he said a surge in depression wasn't inevitable and there were things we could do to mitigate the mental and emotional impacts of the epidemic.

"It's about skills not pills, and our behaviour and lifestyle choices has a very big impact on our mental health."