I worked 100-hour plus weeks as a hospital doctor in the early 1990s. Those dangerous rotas left me low and unable to string a sentence together, let alone give sick people what they needed. Doctors’ crazy hours were reduced, but it seems they may be returning with the new junior doctors’ contract.

Meanwhile, David Cameron will head to Brussels for EU negotiations, planning to insist that UK workers should continue to be able to opt out of the 48-hour maximum working week. Long working hours are on the agenda.

But what about tackling the issue at its roots? What if everyone had a shorter working week? We would be healthier and happier, and society would be less unequal and more sustainable.

It has probably never entered the heads of most economists that hours could be shortened and output maintained

A top public health doctor recently said that long working hours was a big cause of mental ill health, and a big 2015 study linked long working hours with an increased risk of stroke and heart disease.

Less time at work would mean more time to care for children and family, be a school governor, look in on elderly neighbours, or organise a game of football. It would mean more time to create the community spiderweb of connections and favours and reciprocation that keeps the world going round.

More than 6 million of us in Britain work more than 45 hours a week, while 1.85 million of us are unemployed. While it would need to happen gradually, alongside some reskilling and training, a shorter working week for all would mean fairer distribution of available work. It would reduce the number of people working far too many hours, and also the number with no work at all.

For people on lower incomes, it would have to go hand-in-hand with a living wage – something that Britain now agrees on, across the political spectrum. For higher earners, it would fulfil pent-up demand – in London, for example, only 3% of jobs with average or higher salary levels are advertised as part-time, according to Timewise Foundation.

It would help with gender equality too, as men would have more time to look after the kids and the house. About 85% of in-work British men work more than 30 hours a week, but only 57% of in-work women.

Shorter hours could also help mitigate climate change. According to a report from the US Center for Economic and Policy Research, reduced greenhouse gas emissions go hand-in-hand with shorter working hours for a variety of factors including lower levels of consumption.

With all these benefits, cutting the working week should be at the top of every politician’s agenda. But it bumps up against some big prejudices. Would the economy fall apart? How would our open-all-hours society function? And wouldn’t we turn into a nation of couch potatoes?

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The quick answer to all this is to look at other countries. People in the Netherlands work five hours a week less than in Britain, according to the OECD, and in Germany six hours less. The Dutch and German economies are doing fine, and the Dutch people are better known for their love of cycling, than their inability to part from their sofas.

Productivity – output per working hour – improves with shorter hours. Across the world’s richest countries, higher productivity correlates with lower working hours (see also OECD data). Ford’s original workers were found less productive working more than 40 hours a week, a situation likely to be even more the case for people who work with knowledge rather manually – who ever had their best ideas when they were exhausted?

All this means that we may well be able to work a shorter week and get just as much done. The 20th-century British economist John Hicks said:“It has probably never entered the heads of most economists … that hours could be shortened and output maintained.”

It is true that some workplaces, such as restaurants and hospitals for example, would not be able to run nine to five, Monday to Thursday. Tackling this is simply a management issue, and the result would be a better sharing of available work.

Perhaps the biggest obstacle is cultural, rooted in the Lutheran work ethic and our self-valuation according to how hard we strive. It is challenging to tackle such deep-rooted social and personal norms. But given how exhausted many of us are by the end of the week, and how welcome the idea of more time caring for our loved ones, our communities and ourselves (the side of life that cannot be made more “productive”) – it seems like a challenge worth taking on.

A shorter working week is being tried in Sweden, where some care homes and hospitals are experimenting with a six-hour day, and in companies such as Serps Invaders, an Edinburgh digital marketing company where all staff work four days a week (and can also work remotely, and take a day’s leave without notice).

It’s not a new idea – John Maynard Keynes predicted in the 1930s that by about now, we would all be working a mere 15 hours a week. It’s about time we got on with it.