People taking sick days because of work-related stress or burnout is costing the UK economy £28 billion a year, according to new research which highlights the financial toll of poor mental wellbeing.

More people said they were struggling in the UK than in any other nation, the survey of 30,000 adults across 16 European, Asian and American countries by insurer Axa UK and the Centre for Economics and Business Research (Cebr) found.

More than a fifth of UK adults reported being in emotional distress, defined as “struggling”, compared to 17% in the US, 14% in Japan and Ireland, and just 5% of respondents in Thailand.

A further quarter of people said they were “languishing”, indicating that nearly half of people in Britain were not in a positive state of mental wellbeing.

People taking sick days because they feel stressed, burnt out or have generally poor mental health is losing UK businesses 23.3 million working days, the analysis found.

Furthermore, data from Cebr showed that financial concerns among employees are costing UK businesses up to £6.2 billion alone in sick days and lack of productivity, amid mounting cost-of-living pressures.

But while the economic impact is important, it should not be the “driver” for employers to look after their staff, Axa UK and Ireland’s chief executive told the PA news agency.

“For the more hardnosed people, there is an economic value to looking after people’s mental health,” Claudio Gienal said.

“We know that if employees are flourishing, they are much less likely to resign – our research showed that only 6% of people who identified as ‘flourishing’ said they intend to leave their jobs in the near term.

“So if you have lots of people struggling, then it does not make sense economically – they are more likely to be off sick, they are less engaged, and they will move jobs.

“So there is a good rationale economically, but I don’t think it should be the driver.”

Mr Gienal said it is important to “be kind” to people first and foremost, and that fostering a good culture within an organisation is critical to allowing people to be themselves.

However, public sector workers were more likely to experience burnout or work-related stress, the research found, with health and social sectors more likely to feel worried about their job.

It comes amid chronic staff shortages across the NHS that has piled pressure on staff, leading to the Government to pledge to drive recruitment across the health service.

Furthermore, the number of Britons off work due to long-term sickness reached record levels in the three months to January, according to official figures from the Office for National Statistics.

Employment numbers have languished far below their pre-pandemic levels, harming the UK’s already-struggling economy.

Nevertheless, there were signs of improvement in the UK with more people saying they had very good mental health compared to last year, Axa UK and the Cebr’s data showed.

Mr Gienal also noted a decline in the stigma associated with having a mental health condition across the nation.