Rosie Boycott is Chair of the London Food Board and Mayoral Advisor on Food. She is also a journalist who co-founded Spare Rib magazine and was the Editor of Esquire, the Independent on Sunday, the Independent and the Daily Express.

Obesity, food poverty, waste, poor pay – the list of London’s food-related problems goes on and on. But cities will be where solutions are found.

What do you think of when you think about a city? Buildings, shops, cultural institutions, bricks and mortar, roads and parks? But cities are not just bricks and mortar. They are made up of people who are reliant on the natural world to feed them.

When I think about London, increasingly, I think about food and the miraculous role it plays in the life of the capital. Every day, in our amazing city, something like 33m meals are eaten. Just think: all that food has to be grown, harvested, transported, processed, packaged, sold, cooked, eaten and then disposed of. It’s one of the daily, unseen and unappreciated wonders of modern life and it creates over half a million jobs, turning over £20bn every year. It is a feat of such mind-boggling complexity and logistics that it is no wonder that governments – pretty much since the dawn of time – have been happy to hand the problem over to the private sector.

And while the system could be said to operate efficiently – none of us is actually starving, although, shamefully, many of us are malnourished – it is also a system that has run out of control and is now making almost as many of us ill as it makes well. And the development of cities is, I believe, the main reason why.

The origins of agriculture are obscure, but cities could not have been built without it. If you were a hunter-gatherer, you had no use for permanent settlements: you were constantly on the move looking for food. But, around 10,000 years ago, in the fertile triangle of the Middle East, our early ancestors discovered that you could harvest grain and – crucially – store it. They mashed it up in a paste, creating the world’s first bread. It probably tasted weird (and early settlers had terrible teeth) but it was a game-changer.

Railways, canning and refrigeration put an end to cattle and sheep walking along smart city thoroughfares and carts passing people’s houses loaded with potatoes

Grain could be stored in large enough quantities to allow some people to stay put; and from the first tiny settlements in Palestine, cities grew according to how much food they could extract from the surrounding countryside. Rome, the first city to have a population of one million, was also the first city to import food by sea from far away, including oysters from Britain – the world’s first food miles.

At any time before the industrial revolution, London’s streets would have been packed with carts and wagons carrying vegetables and grains, the docksides lined with cargo boats and fishing boats; back gardens would have housed pigs, sheep and cattle; and animals would have been walked to their death in Smithfield, herded across the bridges and along the narrow surrounding streets. Cattle walked from as far away as Scotland, losing up to 100lbs in weight on the journey: they would be fattened up again in the suburbs, usually close to breweries so they could eat the spent grain. Islington combined fattening with dairy farming. At its peak the London ‘herd’ numbered around 20,000 and milkmaids would rise at 3am to milk and then carry the milk into the city. It wasn’t at all hygienic!

If you were living in a city like this, you would have had no doubt about what actually constituted food or where it came from. That was all to change with the industrial revolution. Railways, canning and refrigeration put an end to cattle and sheep walking along smart city thoroughfares and carts passing people’s houses loaded with potatoes. Food in its unadulterated form vanished from our streets and from our imaginations. Food was sold in shiny, ultra-clean shops. It became a commodity.

As food became increasingly industrialised, it also became cheaper. When I was a child, food accounted for around 30 per cent of a household budget. Today, it’s less than 10 per cent. That gap was brilliantly (and maybe ruthlessly) exploited by the growing consumer economy of the 1970s and 1980s. Politicians love cheap food – who can blame them? But did we let food get too cheap, sacrificing health over profits? Now that we’re confronting the biggest health crisis of our times, everyone is asking: how we can reform the food system? How we can bring people back in touch with what they eat? How we can help them understand that what they put in their body really does matter? National government, I would argue, is in a difficult position: the big food companies are brilliant lobbyists; they employ large workforces and their marketing budgets dwarf anything the government can spend to counter their messages with adverts for healthy eating. Food — growing, refining, production, packaging, distribution — is divided up between many industries and it’s hard to say who (if anyone) is actually in control.

And cities and citizens are paying the price in obesity, ill-health, waste and environmental impact. Food banks and food poverty shame our ultra-rich city, as does the prospect of a generation of children growing up into obesity, facing a lifetime of diabetes and other health problems.

It doesn’t have to be like this. Cities have taken leading roles in sorting out hunger and food adulteration in the past and now we must do it again. We will always be dependent on others for the food we eat, we will always be operating on restricted budgets, but now we are paying a price that is too high – and, it is clear, central government is at a loss. There is no single law or measure that will reform our broken food system. As McKinsey pointed out in their groundbreaking report of 2014, at least 80 changes need to be made before we will create a robust food system in which eating healthily is the easy option.

When cities look to national governments, they are met by blank stares or shrugs. The good news is that a new urban politics is emerging, gradually recognising the need to move beyond the neoliberal era’s commitment to cheap and plentiful food, which has spawned new and horrible challenges that the food system cannot itself resolve. Many of these fall to the locality to deal with: waste, the new food poor, rising obesity, street litter, inequalities, poorly paid food work. Positive ideas about how to arrive at a sustainable future need to be grasped: sourcing food closer to home, better jobs, healthier populations.

We managed to turn 160 derelict acres of London into vegetable beds, involving over 180,000 volunteers

The good news is that London is already leading the way. There are countless (and I use that word deliberately) incredible food projects bursting from streets, parks, community centres, markets, homes, schools, cafes, restaurants and hospitals. There is an army of people, supported by brilliant organisations, who understand that food really does matter, not just for our health and environment but also for our wellbeing, our families, our culture and our sense of belonging. In the last few weeks, I have visited social enterprises that are filling the gap left by the ever-contracting state and delivering meals on wheels to the elderly. Provision of meals to homes can keep an old person out of hospital and in their own house for much, much longer – yet, during my time in this job, I’ve seen council after council shut down their meals services in the effort to save money.

Social enterprise is also filling the food poverty gap in the form of social supermarkets, which sell surplus food from the big supermarkets for around 20p in the pound. In return for a six-month membership, you agree to take employment advice and help. Schemes like these really work, yet, to date, they’re not part of mainstream policy.

London has done good work on carbon reduction in energy but, so far, food has escaped scrutiny. This needs to change, not just for our city, but for the country too. Currently, the CO2 emissions of green beans grown in Kenya appear on Kenya’s balance sheet but, increasingly, developed cities are realising that those emissions should rightly belong on their own bottom line. Food accounts for 30 per cent of all the carbon emitted in London. The good news is that cutting it back by, say, 20 per cent would not only be relatively easy but would also be a big step towards a healthier food system. In its simplest form, a 20 per cent cut would entail increasing consumption of local and seasonal veg, reducing consumption of processed meat and all processed food, clamping down even more firmly on waste and restricting the importation of out-of-season fruit and vegetables.

Obesity plagues our poorer boroughs, walking hand-in-hand with poverty, shaming all of us. At City Hall, we have been working to put gardens into every London school, in addition to coordinating with the school meals team and with individual schools to ensure they serve the healthiest food. But this is far too little. It shocks me that fast food outlets regularly drop their prices between 3pm and 4pm to appeal to schoolchildren. For a sum as small as 75p, they can guzzle up a bag of oily chips on their way home. There’s no law we can use to prevent this: as with the vital need to curb food advertising and promotion to children more generally, we need government intervention. Cities can do a lot – but there are many parts of our complex food chain that need legislation: a sugar tax, a mandatory reduction on the amount of sugar in processed food, a law that allows for fast food outlets to be relicensed only if they serve healthier food, for starters.

One of the projects I’m proudest of is our Capital Growth scheme. We launched it in 2008, with the ambitious target of creating 2,012 community vegetable gardens by the end of the Olympic Year. Looking back now, it was an extraordinary ambition, but 10 days before Christmas 2012, I turned over the earth in our 2,012th community garden in The St Charles Hospital in North Kensington. We managed to turn 160 derelict acres of London into vegetable beds, involving over 180,000 volunteers. And the good news is that they’re all still there and that there are many, many other community garden schemes all across the city. (See Kath Dalmeny’s Essay on page 54.) Visits to the Capital Growth sites have been among the highlights of my job: seeing a trashed and forbidding area between tower blocks – once a no-go zone for the elderly or mums with kids – turned back into an area for everyone, the result of a small investment in a community garden in the corner. I’ve met older folk who’ve told me that they had hardly left their high-rise flats for years until the garden arrived: now they’re helping teach the youngsters how to plant and nurture seeds.

In the eight years since I started this job, there have been really significant changes: in the scale of urban agriculture, in efforts to address food poverty, in the proliferation of small artisanal businesses, in the growing numbers of people making food – such as cheeses and sausages and ales – right in the heart of the city. But the biggest change of all has come about in attitude. From all sides of the political spectrum, people understand that food matters crucially to our health and wellbeing. It is this shift in attitude that will eventually bring legislative change and put pressure on the market.

Good nutrition underpins a successful economy: it’s critical for children during their early years, and for all of us to prevent absenteeism at work and encourage productivity. Tackling the twin spectres of food poverty and obesity could deliver economic benefits worth some £17bn a year, not to mention the improvement in wellbeing it would deliver and the sheer pleasure it could bring into all of our lives. I’m very proud to be part of the movement.