urban
HEALTH
ities are crucial
to public health.
They are sources
of cultural, technological and
economic innovation, but they
can also be breeding grounds for
injustice, disease, environmental
destruction, and violence.
By 2030, they will be home to
seven of every 10 humans on the
planet. Through history, urbanization has changed our understanding of public health, and
today, there is an emerging paradigm based on human life in cities. We now know that health and
well-being are not only a matter of
access to medical services, but are
determined by the social conditions—dictated by political, social-cultural and economic forces—in
which people live, work and age.
Building a healthy city therefore
requires access to good-quality
housing, public transportation,
education, work, recreation, and
cultural facilities. Social protection and a healthy environment
are equally important. Finally,
equity—or, the fair distribution of
these assets—is crucial to overall
urban health.
Urban social injustice is epitomized by shantytowns and squat-
C
60 Americas Quarterly FALL 2009
Dr. Daniel Becker
ter settlements. Today, these are
home to approximately 1 billion
people, and that number may double in the coming decades. But
shantytowns are also motors of
urbanization. In their constant
search for opportunities, residents
generate a variety of new enterprises—economic, cultural, educational, and social—as well as strong
social support networks.
The urban environment affects
human health in three principal
ways. The first is related to the
social and behavioral impact on
individuals—their eating habits,
levels of physical activity, sexual
practices, safety, and drug use. The
urban poor have limited access to
information and services, an abundant supply of high-caloric and processed foods, and living conditions
that don’t favor healthy behaviors.
This results in higher rates of diseases such as obesity, hypertension,
heart attacks, diabetes, and cancer. Migrants’ loss of connection
to their original cultures affects
mental health, which is connected,
along with corruption, police brutality and inequality, to high rates
of urban violence—the primary
cause of death among persons aged
15 to 45 in Brazilian cities. Likewise,
vulnerability to AIDS among urban
residents is associated with poverty, gender inequality and access to
education.
The second is related to the
physical urban environment itself.
Poor living conditions favor disease transmission and increase the
risk of contact with contaminated
air, water, food, and soil. Respiratory disease caused by air pollution kills thousands of people each
year in cities such as São Paulo and
Mexico City (and 130,000 world-wide). The planet’s 800 million
cars pollute the atmosphere and
kill approximately 750,000 people
every year due to accidents.
Climate change is the third factor. Three-quarters of global greenhouse gas emissions come from
urban centers in developed countries. Yet it is these cities’ residents,
especially the poor, who will suffer
the most from the likely effects of
global warming: heat waves, insufficient supplies of water and food,
changes in infectious disease patterns, and rising sea levels.
Questions of injustice and
inequality are intimately related to
both the quality of the urban environment and health. In São Paulo,
the wealthiest sections of the city
have 176 times more green space
than poorer sections. Poorer neigh-
