‘DON’t tell me what you value – show me your budget and I’ll tell you what you value.” New Zealand’s government made its values clear when it set out the world’s first wellbeing budget matched by a record £1 billion investment in mental health.

As he presented his budget to the New Zealand House of Representatives, finance minister Grant Robertson challenged his colleagues to consider why, when GDP was rising, all of the indicators of the things that they valued, such as child wellbeing, housing and mental health, were going backwards.

Robert Kennedy once said that “GDP measures everything, except that which makes life worthwhile”.

In publishing its wellbeing budget, New Zealand didn’t simply increase funding for mental health – it acknowledged that the wellbeing of its people is the true measure of a nation’s success.

For the first time, wellbeing underpinned the entire budget process. Crucially it made the connection between wellbeing and departments right across government – from justice, education, the environment, welfare and housing to, ultimately, the economy.

All told, mental ill health costs Scotland around £11bn a year. In 2017, more than one and a quarter million working days were lost due to self-reported work-related stress, depression or anxiety – that’s around half of all working days lost due to ill health that year. Unless we shift our focus from treatment to prevention, rising care costs will become unsustainable both for employers and the government.

We need to look at other approaches. Dr Gary Belkin is the architect of the ambitious $850 million “Thrive” mental health model that’s being implemented in New York City. He told me: “Prevention can be a hard sell, especially when you walk out the door and see homeless people lying on the street – people want the most visible problems fixed fast.”

Politicians the world over want easy fixes and tangible wins as they face scrutiny from their opponents, the media and public opinion. But these quick fixes rarely address the root of a problem, nor do they achieve transformational change.

Thrive New York City, on the other hand, takes a different approach to ill health. Its 50+ initiatives are mostly managed by teams beyond the health department – that alone speaks volumes.

Firstly, it targets the whole population. Each year one in four of us will experience a mental health problem. And it could happen to any one of us – hence why Thrive’s strategy is universal.

Secondly, it takes a holistic approach, and works across government departments including police, housing, employment and child welfare. It also integrates mental health services into programmes already serving low-income communities, where people may not know they need help, or are reluctant to access it.

Finally, Thrive promotes “task-sharing” whereby non-clinical staff such as teachers, police officers, community workers and families are upskilled in supporting those with emotional health issues By investing in mental health we can tackle some of the biggest challenges of our time – homelessness, domestic violence, social isolation, offending and Scotland’s drug issue.

In the run-up to the next Scottish Parliament election, we need a conversation on what we want our public health system to look like.

Let’s put mental health and wellbeing near the top of every cabinet secretary’s agenda and publish our first wellbeing budget. In the long term, every one of us will reap the rewards of a healthier Scotland.

Toni Giugliano is policy manager at the Mental Health Foundation and programme affiliate at New York University