During my pediatrics rotation, I met a 13-year-old girl with obesity. She was trying to follow her doctor’s advice to eat healthier and exercise more, but it was tough: She lacked access to a gym, her neighborhood lacked sidewalks, and local traffic was fast and busy. It was not safe for her to walk or rollerblade alone, despite her motivation to be more active.

Her problem is a common one in the United States, where the built environment has made it difficult to incorporate activity in our daily lives. Due to the way certain cities and suburbs are designed, prioritizing enjoyable time outdoors and accessible daily movement without relying solely on gym equipment is not feasible for many.

Miami, where I live, has many examples of how the built environment limits us. Dangerous intersections, inadequate shade, and lack of pedestrian infrastructure keep people indoors or confined to cars. A 2022 report ranked Florida the second-most deadly state for pedestrians. Walkable neighborhoods tend to be more affluent, but these community benefits should be widely accessible. Urban planning that prioritizes people over cars should be leveraged to improve health outcomes and promote health equity.

How did we get here

Knowing the history of our built environment is critical for understanding how it affects us today. America was not always a land of sprawling suburbs. In the early 1900s, many American cities were walkable with robust streetcar public transit. However, as cities grew and the post-World War II GI bill prioritized new low-density construction, suburbanization exploded. The booming automobile industry and federal highway investment prioritized cars as the primary form of transportation, and streetcars soon fell out of favor.

Although these advancements increased mobility, they worsened pedestrian safety. In many cases, they also exacerbated segregation and neighborhood disparities. Highway construction was often routed through poor and Black neighborhoods. In Miami, construction of I-95 through Overtown, a once robust and bustling Black neighborhood, displaced thousands and permanently disrupted the community. As development progressed, the country built cities around cars, not the overall well-being of people and communities.

What does this have to do with our health

This history has insidious consequences on our health. The leading cause of death in the United States is heart disease, which is often associated with high blood pressure, diabetes, and obesity. These conditions are often related to lifestyle choices such as diet and exercise. This means that many daily decisions affect our health. Where is the nearest supermarket with fresh produce? Is it within walking distance? Is there a safe place to go for a jog? For many Americans, the ideal options are not available due to structural limitations. One in six live in a food desert, meaning they don’t have convenient access to healthy food. For my patient, there was nowhere nearby where she could safely walk or rollerblade because her neighborhood was built for car traffic, not pedestrians.

What can be done about this

Studies show that the more walkable a neighborhood is, the more active the people who live there are. They also have lower risk of having obesity and diabetes. Changing city infrastructure to promote healthy lifestyles seems like a big ask, but it is possible. Oklahoma City, once named the 8th fattest city in America by Men’s Fitness magazine, successfully made these changes in 2012 under the direction of then mayor Mick Cornett. He recounts that “I started examining my city, its culture, its infrastructure, trying to figure out why our city seemed to have a problem with obesity. And I came to the conclusion that we had built an incredible quality of life if you happen to be a car. But if you happen to be a person, you are combatting the car seemingly at every turn.” Through sales taxes, bond issues, and corporate donations, the city built more recreation centers and hundreds of miles of sidewalks and bike paths. Along with a city-wide campaign for healthier food options, about 47,000 residents enlisted in an online effort to track progress and cumulatively lost over 1 million pounds.

To be sure, such infrastructure overhaul requires significant financial investment and political willpower which may not be feasible everywhere. More active lifestyles are not guaranteed to prevent all disease, and building more sidewalks will not fix health care disparities. However, the evidence is clear that improving neighborhood walkability can help people make better lifestyle choices.

Furthermore, leveraging the built environment to improve health does not require overhauling city infrastructure. Modifying existing construction and using approaches including community programming and slow traffic policies can have meaningful impacts. The Miami Underline, a 120-acre, 10-mile urban trail park that runs below Miami’s elevated light rail, is currently under development. It will serve 107,000 residents within a 10-minute walk, with access to protected pedestrian and bike paths, gardens, and various recreational features. This space, once previously undeveloped, is an example of modifying existing infrastructure to benefit community well-being.

Where do we go from here

The scope of public health reaches beyond vaccinations, epidemiology, and policy. Understanding how the space we live in affects us is critical for improving population-level health outcomes. As community members and health practitioners, we must advocate for policy and funding that creates more pedestrian-friendly, safe, and accessible green space, especially in neighborhoods that need it the most. It would be incomplete to continue recommending that patients make lifestyle changes for their health if we do not concurrently work to improve the built environment within which they must make these changes. People like my patient deserve better.

Karen Zhang is a medical student.