Table 1 Selected urban health challenges

Non-communicable diseases (NCDs)

Where urban form is associated with sedentary lifestyles or increased consumption of unhealthy foods, city dwellers are at higher risk for obesity and associated NCDs, including heart disease and stroke, hypertension, diabetes and some cancers. Urban air pollution can impair lung function and give rise to or exacerbate cardiovascular and respiratory diseases, including asthma, in acute and chronic forms. It can also contribute to the development of allergic disease or cancer and cause adverse pregnancy outcomes.

Infectious diseases

The high concentration of humans in cities naturally promotes increased transmission of some infectious diseases, such as tuberculosis. Growing mobility within and between cities and urban expansion into natural habitats contribute to ever-more-rapid emergence and spread of infections.

Accidents and injuries

City forms that encourage automobile use, often in combination with inadequate safety regulation, contribute to higher rates of road traffic accidents and deaths.

Mental health

The urban built environment can adversely affect mental health. For example, lack of public space for recreation and socialization can lead to isolation and depression. Noise pollution and commuting can create significant stress.

Disaster risk

Cities are often built in high-risk areas, such as along coastlines and rivers or on hill slopes. In particular, poor informal settlements often take hold and expand on otherwise unwanted land at high risk, such as on floodplains. Urban expansion can compromise fertile agricultural land, decreasing food security.

Climate change

Long-term urban impacts on climate can harm health directly (e.g. through increases in acute heat waves or other extreme climatic events) or indirectly (e.g. through shifts in vector ranges or resource availability).