Working one day a week is the key to the best mental health, new research suggests. Researchers at the universities of Cambridge and Salford set out to find a working pattern that would be most beneficial to employees' mental health.Their findings, published Tuesday in Science Daily, reveal working any more than 8 hours a week provided no additional boosts to mental well-being."We know unemployment is often detrimental to people's wellbeing, negatively affecting identity, status, time use, and sense of collective purpose," study co-author Dr. Brendan Burchell said. "We now have some idea of just how much paid work is needed to get the psychosocial benefits of employment -- and it's not that much at all."The project examined more than 71,000 working-age people in the United Kingdom from 2009 to 2018, and participants were asked about issues such as anxiety and sleep problems to gauge mental health."The traditional model, in which everyone works around 40 hours a week, was never based on how much work was good for people. Our research suggests that micro-jobs provide the same psychological benefits as full-time jobs," co-author and Cambridge sociologist Senhu Wang said.