Richard Joseph Jackson, MD, MPH
Director, National Center for Environmental Health
Center for Disease Control and Prevention
Medicine alone will be inadequate to deal with the health challenges of the 21st century, even with the help of the sequenced genome and advances in robotic surgery. Despite the United States’ expenditure of more than one of every seven dollars on medical care, the prevalence of chronic diseases, and the costs for their care in an aging population, will continue to increase. Of the strategies to limit these burdens, none will be as cost effective and improve the quality of life more than giving much more attention to how we plan and design our living environments. Healthy living environments include not just a clean and heated kitchen, bath or bedroom, but also the structures and landscape around us. Health for all, especially for the young, the aging, the poor, and the disabled, requires that we design health-fullness into our environments as well. During the nineteenth century life of Frederick Law Olmsted, the nation’s greatest landscape architect, the average American’s life span was less than 40 years. Today, it is 80. Surprisingly, only seven of the added years are the result of better disease care. The rest comes from efforts that Olmsted would have understood perfectly: broader immunity to disease combined with higher living standards and a healthful environment, including clean water and food, and better and safer housing.
Of the many challenges of the 21st century, the major one for planners and designers will be good design for density. As we look around the nation today, we are staggered by population spread. We can drive the megalopolis from Norfolk, Virginia to Portland, Maine and scarcely see an open field (unless it has been protected as public land). Yet, the Census Bureau estimates that the US will double its population again in this century—a whole new nation added --600 million people! Designers and architects will be required to design for quality density.
This population increase brings new challenges for those in public health who work to make the nation healthier. The health challenges of the 21st century include assuring a healthy aging population, protecting mental health, thwarting environmental threats, preventing and controlling chronic diseases such as diabetes and obesity, and eliminating disparities such as diminished health among the poor. To address these challenges, we will need to be much smarter about how we use the land and design our housing and landscape.
This is particularly true as we work to end the disparities in health and survival between the rich and the poor. Economic favor is reflected most in the overall quality of our environments. For example, in Los Angeles housing cost is highest in areas of the city where air quality is best. It is not just a social equity goal, but also a health goal, to have communities where rich and poor can live where there is good public transportation, accessible parks, sidewalks, and public areas.
As an epidemiologist who has investigated disease outbreaks of all kinds, I have seen the links between how we design our living environments or use our land and the origin and magnification of disease events. For example, water treatment alone will not fully prevent transmission of diseases in drinking water. Rather, protection of the sources of drinking water-- the rivers, lakes and groundwater--will also be essential. Thus, land and water protection is therefore health protection, now and for the future. The same is true for air quality: ozone alerts, heat island effects, particulate air pollution cannot be solved by mere “Ride-Share” programs. Focusing on how we build, insulate, and cool our homes, and how efficiently and cleanly we can be transported to home, work, and school, will determine whether air quality is fit enough to go for a walk or a run.
An example of a disease problem epidemic that is exacerbated by bad environmental designs is that of the epidemic of obesity in the US. Twelve per cent of the U.S. population was obese in 1991; 18% was in 1998. Obesity is unhealthy, it raises risks of heart disease, high blood pressure, diabetes, stroke, and diminishes vitality. For diabetes, from 1980 to 1994 the prevalence in the population increased by 2.2 million cases, an increase of 39%, and diabetes is the 7th leading cause of death in the US. Type 2 diabetes (formerly only associated with older and often obese adults) has increased in every age group in the population. Lack of exercise, or any physical activity, contributes to obesity and diabetes epidemic. Despite common knowledge that exercise is healthful, fewer than 40% of adults are regularly active, and 25% do no physical activity at all. The way we design our communities makes us increasingly dependent on automobiles for the shortest trip, and recreation has become not physical but observational. There is increasing evidence (though much more research is needed) that contributing to the obesity epidemic is the lack of safe and healthy places to pursue even the most basic physical exercise, walking. Walking does not require steel, gasoline, or a catalytic converter. It is a socializing and safe exercise for everyone, and the prime exercise for the elderly.
Changing the environment can change health, profoundly for good or ill. In the 1970s the heavy metal lead had thoroughly contaminated our environment, and our own developing brains, and its removal seemed an insurmountable task. Fifteen years ago, as a representative for the American Academy of Pediatrics in Congressional testimony, I asserted that lead poisoning was “the number one environmental health risk to children in America”. Changing the environment, removing lead from gasoline, paint, food containers and other sources, has been astonishingly successful in lowering the lead levels in all Americans, most importantly in the developing brains of children. But not all children have benefited equally. Today, the children with high lead levels are ones who are poor, often malnourished, and live in deteriorated lead-painted houses. These same homes are risky for reasons other than old lead paint: they often have insect and rodent infestations that contribute to lung and other disease. Wiring, plumbing, insulation are usually dangerous or inadequate and contribute to fires and injuries. The healthier community designs of the future will need healthier homes as well.
As we look at respiratory risks to our children, asthma looms large. In some schools as many as 30% of children carry inhalers and are said to have asthma. Despite genuine advances in medical care and drug therapy for asthma over the last 20 years, there has been a stairstep climb in asthma cases nationally, with deaths increasing as well. The causes for these increases are not known for sure, but indoor allergens and outdoor air pollution do raise risks for both developing the disease, and for setting off asthma attacks requiring and hospital visits. Every asthma specialist recommends lowering dust and allergen loads in the home, followed by removing pets, carpeting, curtains; by covering mattresses and pillows, and by changing or improving air filters. Clearly good indoor air quality is a problem that designers, architects, and builders can solve. There are reliable and effective systems for replacing bad indoor air with heat-exchanged filtered outside air in a well-sealed building – and not by pulling air into the house from moldy areas like crawl spaces and. Such measures usually reduce home radon levels as well.
While outdoor air is nearly always cleaner than indoor air, outdoor air pollution is associated with asthma attacks. In Atlanta following Ozone Alert days, emergency room visits increase by 30 to 40%. The largest contributors to outdoor ozone production are pollutants coming from vehicles and power plants, particularly on hot days. Cooler landscapes with light colored paving and roofs, with more shading and trees, can reduce ground level ozone effects and electrical power demand. This coupled with better housing design and insulation would generate less power plant emissions. At the same time commuters are not going to reduce their automobile use until they have access to sidewalks, bicycle routes, and reliable and safe mass transit systems. The tree shaded streets and neighborhoods that Olmsted demanded, are the same streets our power demands require.
Mental distress, particularly depression, is epidemic in modern American society. Prescriptions for SSRI antidepressants have climbed each of the last 15 years since they were first marketed. Depression is associated with lowered levels of the hormone serotonin in the brain, and exercise can increase these levels. Some research is showing exercise to be as effective as SSRI’s in raising serotonin levels. There is also some research showing more rapid recovery of ill persons in the presence of green landscape, though more research is needed. Human beings need to walk and “re-create” themselves in safe and refreshing environments, Olmsted knew this. As a man coping with his own tendency to depression, he spent two trips to Europe studying landscapes that attracted and revitalized people, and was himself revitalized.
Tasks that in other cultures were refreshing, socializing and enjoyable have become in America burdensome and stressful. At the same time that children’s days are being filled with increasingly more programmed activities—school or day care, dance and music classes, library work or sports practices— their parents transport them by car. These children are being cheated of unsupervised but essential socializing with peers on the way to school. Many children also see too little of their loved ones. Because of parents’ long commutes to work, many pre-schoolers never see their parents during daylight hours on workdays. These demands, combined with long commutes, lack of reliable mass transit, and inevitable traffic tie-ups are a recipe for stress. “Road rage” is not imaginary; every commuter can describe an unpleasant and disturbing encounter in the past year. Mental stress, with outcomes ranging from sleeplessness to outright violence, is a serious health hazard. Better public transport and putting density in our housing, with humane live-work-play community designs, that put people on their feet rather than on their seats, might help reduce aggressive driving which causes in 1500 fatalities each year.
Urban design that offers the benefits of more walking, more social contact, surroundings that include water and vegetation, can offer healthful physical exercise and psychic respite. Look at a child who gets up from video activities, often they are aggressive and provocative. Contrast this with the same child after a bicycle ride: they are usually smiling.
Columbia University Psychiatrist, Dr. Mindy Fullilove, studies the effects of disordered physical environments on mental and physical health. She has asserted from her studies throughout the United States: “disordered environments make people crazy”. Physical environments can either leave people feeling vulnerable and anxious, or in re-vitalized contact with others and the world. Dr Fullilove has found that Harlem residents re-occupying apartment buildings that were clean, orderly and “defensible” showed improved physical and emotional health, including benefits like lower blood pressure.
Frederick Law Olmsted was not a trained specialist in landscape, public health, agriculture, or social reporting, although he excelled in each. Perhaps, because Olmsted was not blinkered by over-specialization, he could more readily see the connections between health and human circumstance. As head of the US Sanitary Commission early in the Civil War, Olmsted demonstrated the benefits of disease prevention as a social and practical good. Military physicians at first thought him a meddler when he demanded and provided clean water and safe food for wounded soldiers. It was not until he demonstrated better survival and more rapid return of the injured to service that the Army adopted his “radical” hygienic methods. Olmsted profoundly understood that the parks and campuses he and colleagues designed were for human well-being: cultural, physical and social. He instinctively knew that the architect and the landscape designer, the road builder and the house builder, were contributing as much as any physician—perhaps more--to the health of all.
"A Clearing in the Distance: Frederick Law Olmsted and America in the Nineteenth Century."
Witold Rybczynski, Scribner.1999
"Rebuilding the Unity of Health and Environment: a new Vision of Environmental Health for the 21st Century." Institute of Medicine. National Academy Press. 2001
Diabetes Reference (CDC)
Obesity Reference (CDC)
Physical activity reference (CDC)