Rapid urbanization. Climate change. Human health.
As more and more people are concentrated into the world’s cities, access to nature and outdoor recreational opportunities is lacking for many. This is helping to drive high rates of obesity and a host of other chronic diseases that are emerging as top public health challenges in the 21st century.
Changing weather patterns threaten to make a bad situation even worse.
A two-day conference—cosponsored by the Yale schools of public health and forestry and environmental studies—drew nearly 200 people to Kroon Hall from across Yale and beyond, including students from a New Haven high school. They heard from panels of experts about the importance of access to nature for physical and mental health and the threat that climate change poses to densely packed and often impoverished modern megacities.
“Something is happening to humanity. We were designed to be connected to nature,” said William Bird, the conference’s keynote speaker and CEO of Intelligent Health, a United Kingdom-based health technology company.
Bird explained the biological consequences faced by many people in modern society. Chronic day-to-day stress (exacerbated by little or no physical activity) over time fosters the formation and growth of visceral fat, which unlike subcutaneous fat, surrounds internal organs. Untreated, it leads to premature death.
Bird noted, however, that there are many people who live in cities who are happy and healthy and many others who live in rural areas who are depressed and in poor health. Natural resources such as grass, trees, water and open space are not a panacea for everyone, but access to such resources can have a profound affect on an individual’s lifestyle and overall health.
“Nature seems to affect those who need it the most,” he said.
Dean Paul Cleary of the Yale School of Public Health told the gathering that close collaborative relationships, such as those that exist between various Yale schools, research groups such as Yale’s Hixon Center for Urban Ecology and CARE: the Community Alliance for Research & Engagement and community partners, present fantastic opportunities to take new research findings and implement them for the benefit of residents.
Cleary linked such efforts to the school’s centennial celebration that is underway this year. Such community-based interventions were very much in keeping with the practice and vision of C.-E. A. Winslow, who founded public health at Yale in 1915.
“All of these papers and grants we write are useless unless we have a positive impact on our neighbors and local communities,” Cleary said.
It is critically important in the face of rapid urbanization to better understand the linkages between nature and peoples’ emotional and physical health and how people can reconnect with nature, he said.
Sir Peter Crane, dean of the Yale School of Forestry & Environmental Studies, noted that the world had rapidly urbanized within the past few decades and that more than 50 percent of the human population (some 3.5 billion people) now live in cities. The percentage is expected to increase even further in the coming decades.
Kristie Ebi, a professor in the Department of Global Health at the University of Washington and a panelist, said that extreme weather events are increasing around the world, often with severe consequences for human health.
She cited recent heat waves in Russia and elsewhere that have claimed thousands of lives. Higher temperatures also affect worker productivity, causing economic disruption for individuals and nations. Higher incidences of diarrheal and vector-borne diseases, such as dengue, are also linked to climate change and take a high toll on human health. Meanwhile, crop yields are falling in some locations due to increased temperatures.
“The climate is no longer stable,” Ebi said.
Michelle Bell, a panelist from the Yale schools of forestry and public health, agreed, adding that ozone levels, both from manmade sources as well as emissions from vegetation, are on the rise. This will contribute to more forest fires, more pollution and, ultimately, worse health outcomes.
Despite the seriousness of the situation, Bell said there is widespread “denialism” among the public about such climatic changes, an outlook that she described as “a crisis.” Communicating scientific findings and evidence to the public is more vital than ever.
Albert Ko, professor at the Yale School of Public Health and one of the conference’s moderators, touched on the issue of social inequality that is widespread in many of the world’s urban areas, including Brazil where he does much of his research. Today, some one billion people live in urban slums, a number that is projected to increase to two billion in the foreseeable future. Health threats are particularly severe for this population.
Panelist Jeannette Ickovics, professor at the Yale School of Public Health and director of CARE, recently studied the link between access to parks and individual health in greater New Haven.
The research found that park access direct affected self-rated health and that park access was related to a variety of positive health outcomes.
People with convenient access to open space and parks are more likely to exercise regularly and as a result have fewer chronic diseases, less depressive symptoms and, overall, reported excellent health.
Ickovics spoke of democratizing nature and making it something that everyone can access and incorporate into their lives, especially urban dwellers with limited financial resources.
“Park access absolutely impacts health,” Ickovics said. “We must preserve and expand access to green space.”
The conference was part of the Yale School of Public Health’s centennial celebration. Founded in 1915, the school is one of the oldest institutions of its type in the United States and today has a wide array of research projects in progress around the world. This is augmented by close to 5,000 alumni who work in virtually every aspect of public health in some 70 countries.