A city should specifically counteract social isolation and loneliness by providing age and culturally sensitive stimulation that motivates inhabitants to venture outside their front door.
Urban planning prerequisites include sufficient public spaces that can be utilised, i.e. pedestrian zones that are not only used for walking, but also as leisure areas, parks, green spaces, with trees, playgrounds, sports and cultural facilities.
People with a higher risk of social isolation (e.g. immigrants, the sick and elderly, people living alone, the poor) must be given special consideration by implementing specific intervention measures tailored to the needs of these risk populations.

Interpersonal relationships are among the most important components of mental health and satisfaction. The ability to enter into and maintain these relationships is regarded as a key competency within the framework of mental health.

Due to the high number of urban dwellers, the city offers many opportunities to build and enjoy interpersonal relationships. Numerous studies have shown that a balanced social network is a protective factor against mental and physical disorders. It is assumed that the adversaries of social inclusion – social loneliness or social isolation – are significant components of pathogenic social urban stress.

Social loneliness is initially the subjective, stressful feeling (emotional pain) of being alone in life (the absence of a sense of belonging). It is objectified by the discrepancy between the actual and the personally desired degree of social inclusion. This varies from one individual to the next. It can also be understood as a biological deficiency signal, which is intended to alert or prompt the person concerned to act in order to ensure their survival.

Social isolation, on the other hand, is an objectifiable lack of friends and confidants, characterised by a lack of communication and active participation in social life. Social exclusion resulting from being socially or psychologically different is regarded as a serious and intensive type of social isolation. Many studies and meta-analyses have convincingly shown that both phenomena are associated with significantly adverse health effects and increased mortality (e.g. high blood pressure, increased blood lipids, immunodeficiency, sleep disorders, smoking).

Urban planning measures and the teaching of so-called "big-city skills" can minimise the risk of mental illness in socially marginalised groups.

Social isolation is one of the most powerful negative health predictors and it influences the prognosis of nearly all physical or mental illnesses. The risk of social isolation is generally higher for city dwellers than it is for people living in rural areas. An above-average number of urban residents have a higher risk of social isolation. These include singles, who are more likely to live in large cities than in rural communities or small towns.

The risk populations also include people with a history of migration. They have a higher risk of social exclusion, which is a particularly stressful and serious form of social isolation. It has been found that people with a migration background have a higher risk of depression, post-traumatic stress disorders and psychotic disorders. A number of studies have shown that, among migrant women, the feeling of not belonging and alienation is a chronic stress factor that increases the risk of mental strain and illness.

In addition to urgently needed urban planning and social responses, risk populations should receive support by teaching urban competence. These so-called “big-city skills” include interpersonal and intrapersonal abilities that help prevent isolation and loneliness while maintaining a sense of control over the living environment. These skills include, for example, an awareness of the availability and location of leisure areas along with coping skills for dealing with stressful situations.

Social loneliness and isolation – especially due to being socially or psychologically different –appear to be a major cause of health-related urban stress.