Standing in the right place, deep within the density of tower blocks and the throng of crowds and the neon glow of kanji, is a snapshot of humanity’s future. We could be on the set of Blade Runner.

But sci-fi films are not the only way to envision our overcrowded, hyper-urban future. Asian megacities offer a present day glimpse of what the world’s soaring population and rising urbanisation could mean for how we will live. By doing so, these cities also hold clues about how to futureproof our sanity.

As more people flock to cities, we need solutions that balance urban density with liveability. Hong Kong and Tokyo are both super-ageing cities known for their tall buildings, long working hours, efficient underground trains, and tiny living spaces. In both cities, stress and loneliness are common complaints, suicide is not uncommon, and at least one in five people experience a serious mental illness in their lifetime. Like anywhere, many factors mediate these risks: genetics, upbringing, employment, certain physical illnesses.

But these one more factor whose impact is only now emerging as a key determinant of mental health: the built environment. Modifying the settings where we live, work and play is not just the next big public health opportunity; it is a key to the resilience that companies, cities and countries seek for their populations.

The built environment affects mental health in two important ways. First, by over-stimulation. Cities can provide social and cultural stimulation that surpasses that of rural settings. Everything we see in cities is designed to make us think, feel or act in certain ways. Many of us left our close relationships behind to move to the city, and instead of someone to confide in, every day we encounter tens of thousands of someones. All of this can result in overload: an urge to retreat from this assault on our senses.

Secondly, cities deplete the very factors that strengthen our mental health and build resilience, such as access to green, natural spaces, regular physical activity, and positive social interaction. As the population urbanises, these challenges risk escalating, to the detriment of society’s mental health and wellbeing.


This hyper-urban future is currently the present in many of Asia’s denser cities. Examining how these cities are adapting uncovers clues about our upcoming challenges and emerging solutions.

Growing density and demand for space drives up house prices unsustainably. In the quest for affordable housing solutions, some people in Hong Kong have had to live in ‘cage homes’, tiny ‘caged’ living spaces within subdivided apartments. And through the challenges of this very constrained living, it is becoming clear that affordability and quality of life can be improved through a return to social, communal facilities, from shared kitchens to shared study spaces.

Developments are encroaching on public open space, so in addition to incentivising developers to provide dedicated public spaces, Hong Kong’s population is improvising, appropriating spaces for different uses at different times. University plazas for older people to exercise at dawn before the students swarm in; the grounds of a major bank building, for migrant domestic workers to socialise at the weekends when office staff go home; and even corners of air-conditioned office lobbies have become informal day centres for older people.

Meanwhile in Tokyo, streets are being flexed as public spaces. Vehicle traffic is encouraged to stick to the bigger roads, and in many places, the smaller networks of roads inside these grids are given over largely to roadside plants (often provided and maintained by local residents), pedestrians, and mothers riding mamachari bicycles with several children strapped aboard, stopping to chat outside small and welcoming shops.

Looking at hyper-dense Asian cities also makes it clear that the future could be public transport – the key to which is seamless integration with safe and convenient pedestrian and bike links between stations and destinations. In Tokyo, hills are tackled with electric bicycles; in Hong Kong with free public outdoor escalators. In both cities, residents benefit from the regular physical activity that is naturally integrated into their daily routines.

Nature is good for our mental health, but dense development makes access to greenery challenging. Tokyo and Hong Kong both incentivise developers with tax credits to green their buildings, and invest in urban parks within new developments. But recognising the land use challenges, both cities also prioritise the provision of cheap, convenient public transport access to large swathes of greenery just outside the city. Whether they call it forest bathing (Tokyo) or simply hiking (Hong Kong), it is clear that to fully reap the mental health benefits of nature, we need both urban nature that people can access in the course of their daily routines, and immersive nature that delivers a bigger respite from the city.

What these solutions have in common is the design of settings that facilitate positive social interactions within dense neighbourhoods, enabling participation of people of all ages in shared spaces. These uses of space enable residents to physically see each other. In doing so, they build their social capital and a sense of community belonging. This is incredibly protective for mental health.

If we look to Hong Kong and Tokyo for clues to our future, it becomes clear that while some parts of our future cities might look like Blade Runner on the surface, underneath we may find a dense collection of overlapping villages.

Layla McCay is director of the Centre for Urban Design & Mental Health.