If you ask your grandmother what pea soup is, she might surprise you by referring to the climate rather than her cookbook. My grandmother came of age in London during the 1950s, a time of significant growth as Great Britain stepped out from the privation of the Second World War as record numbers of imports and exports passed through her docks. New hospitals, houses and schools were thrown up to meet the needs of the booming population, all powered by the relentless need for coal.

It proved to be a toxic mix. Londoners had become so used to the poor air quality that they casually referred to it as ‘pea soup’, but it came to a head in the winter of 1952 as unprecedented city-wide smog descended on the capital for four days. Thousands of people suffered major respiratory problems in the weeks that followed, and some research suggests that as many as 12,000 people died as a result. The tragedy triggered a series of regulations to clean up London’s industries and transport, but for many it was too late. London was just one example of rapid urban expansion in counties all over the world, to which their reputations had been cast: city living was synonymous with poor health.

Fast-forward two generations and my grandmother wouldn’t recognize the kind of city I live in today, just a hop over the water in Denmark. With a commitment to be carbon-neutral by 2030 and with more than 450 km of dedicated cycle lanes, Copenhagen is flipping the very notion of city living on its head by transforming itself into a ‘livable’ city. In practical terms, this means that city officials make conscious decisions which put people at the heart of how Copenhagen infrastructure is designed and deployed – and this is most apparent in its extensive cycle lanes and green routes. More than 45 percent of Copenhagen residents cycle to work or school, lapping up more than 1 million kilometers in total every day. Such a high modal share on the capital’s roads means that car traffic and air pollution is reduced, in addition to the good that comes from an active commute. The Capital Region of Denmark estimates that it has one million fewer sick days each year due to the fact that its inhabitants are regular cyclists.

Therefore, it is no surprise to learn that Copenhagen is continuing its great work by upgrading 380 traffic signals to prioritize buses and cyclists, reducing commuting times by 20 percent and 10 percent, respectively, and thereby continuing to promote healthier, low-carbon transportation. What’s more, this made it one of the city solutions that the research team at Sustainia has flagged as a strong indicator for a new sustainability trend this year, highlighted as part of our annual Sustainia100 – can living in a city be good for your health?

We know that good health has multiple touch points, from the food we consume to the way we get around, all of which form the fabric of our built environments. In ways which mark a ‘liveable’ city out from a ‘smart’ one, the solutions we’ve included in this year’s sustainability guide (which are mapped against all 17 Sustainable Development Goals) show how many cities are starting to use refreshingly low-tech approaches, such as sharing skills and promoting local decision-making, to create better health opportunities for inhabitants. The effect? Healthier, happier and more resilient communities in the midst of our global cities.

One of my favourite initiatives is City Health Works, a Harlem public health programme which bridges the gap between the doctor’s office and the everyday lives of chronically ill patients living in the neighbourhood. Locally hired Health Coaches become the much-needed eyes and ears to overburdened city clinicians, by helping set health goals, giving families the skills to manage care at home for illnesses including diabetes, hypertension and asthma, and establishing relationships that mitigate against health stressors such as poverty and isolation. City Health Works estimates that for one out of every two patients, they have identified a medical issue that was otherwise unknown to the medical provider, before it became a crisis.

Another great example lies almost 4,000 km due South in Medellin, Colombia. Here the local government is involving residents in redeveloping more than 85 hectares of land around the city’s borders to promote health and wellness, contain sprawl, and improve food security. Medellin calls this their Metropolitan Green Belt, and it provides recreational areas, parkland and space to grow food, all of which actively engages around 64,000 community members. The city focuses on involving locals as much as possible, so the benefits go where they are most needed – to date, more than 100,000 newly planted native plants and trees are restoring the local ecosystem, and at least 300 families directly benefit from the agro-ecological gardens. By limiting urban sprawl, increasing air quality, and focusing on access to nutritious food, Medellin is giving residents a truly healthy boost.

These are just a few ways in which cities are helping meet the Sustainable Development Goals, particularly as they relate to the health and wellbeing of the people that live in them. But we still have a long way to go. It is estimated that air pollution has reached unhealthy levels in 80 percent of the world’s cities – particularly the poorest – and urban areas are home to two-thirds of the 415 million people living with diabetes. Current projections show that 70 percent of the world’s population will be urban by 2050, so it is undoubtedly in our best interest to ensure that cities cease to be a strain on individual health, and instead become facilitators for resilient wellbeing for all people at every age.

Back in London, the battle against mounting air pollution is still underway. Just this month, a shocking new report showed that children in as many as 90 secondary schools in the city are breathing illegal and dangerous levels of air pollution. The case for cities to stay on the map is dependent on people becoming healthy because of where they live, not despite it. That starts by making sure pea soup is something you would only expect to find in your bowl at lunchtime, and not in the air that you breathe.

Katie McCrory is the global communications lead for Sustainia.

Sustainia helps public and private organizations create a more sustainable tomorrow, building on the solutions available today. Find out more at www.sustainia.me and follow @Sustainia