Policy and Planning: The Link between the Built Environment and Obesity

While the public often associates urban planning with designating land use for economic development, the design of the built environment also affects the health of those who live in cities.

Incorporating and preserving parks like this one in Savannah in city plans decreases the residents risk of obesity. Source: FGrammen Wikimedia Commons

One of the greatest public health issues facing Americans is obesity. According to the American Heart Association, 35 percent of adults and 17 percent of children and teens in the United States are obese. In addition, no state in the country has an overall obesity rate of less than 20 percent. On the current trajectory, more than 50 percent of American adults will be obese by 2050.

Some of the risks of obesity listed by the Centers for Disease Control and Prevention (CDC) include:

• Hypertension
• High levels of triglycerides and LDL cholesterol
• Type II diabetes
• Stroke
• Heart disease
• Gallbladder
• Osteoarthritis
• Sleep apnea
• Breathing issues
• Liver, kidney, colon endometrial, breast, and gallbladder cancers
• Clinical depression and anxiety
• Chronic pain leading to physical disability

While it is common knowledge that a person’s diet and level of exercise directly influences their risk of obesity, an individual’s living environment also has an impact on their weight.

The Link between Urban Environments and Obesity

Community gardens provide access to fresh fruit and vegetables as well as encouraging physical access. Source: Public Domain, Wikipedia  

While common lore suggests that people who live in cities maintain healthy body weights because they tend to walk to work, school, and entertainment venues, research provides evidence that this is not necessarily the case. The layout of streets, access to recreational facilities, availability of affordable fresh and healthy foods, and the level of community safety perceived by residents all influence the body mass of city dwellers. A brief review of the research provides insight into how urban planning practice have the potential to reduce the risk of obesity.

Street Networks: A 2014 study conducted by the civil engineering departments at the University of Colorado-Denver and the University of Connecticut along with the Savannah State University Department of Urban Studies and Planning found that incidence of obesity is lower when the street network is dense and interconnected than those are spread out. In addition, cities with a compact and highly connected tend to have lower rates of diabetes, heart disease, and hypertension.

Urban Neighborhood Characteristics: The findings of a 2016 Swiss longitudinal research study indicate that areas high concentrations of low-income residents tend to more people with high Body Mass Index (BMI) than high-income urban enclaves. When authors of the study controlled for individual characteristics, including socioeconomic level, the disparity in obesity rates remained the same. Further investigation discovered that low-income urban areas tended to have less green space and fewer, if any, grocery stores, thus limiting access to fresh healthy food. This research confirms the findings of a 2014 review demonstrating that when urban planning practice segregate communities according to income levels, they contribute to elevated rates of obesity. In addition, low-income areas are three to eight times less likely to have access to recreational facilities.

Proximity to Public Transportation and Population Density: A 2007 multilevel analysis published in the American Journal of Health Promotion found that when people lived in densely populated urban areas with numerous bus and/or stops, the incidence of obesity was significantly lower than other neighborhoods.

Perception of Safety: When people perceive their neighborhoods are safe, they are more likely to take advantage of walking trails, according to a 2012 research paper published in Economics and Human Biology. In addition, studies cited in a review by Harvard University’s School of Public Health indicate when people perceive their neighborhoods are not safe, the rate of obesity significantly increases.  

The Role of Zoning and Urban Planning Practices in Reducing Obesity

Research suggests that zoning and land use policies that promote active transportation, such as walking and bicycling, and provides access to healthy foods can help reduce obesity rates among those living in urban areas. In addition, those who lived in urban areas with a mix of income levels tend to have lower rates of obesity, which points to the value of incorporating mixed-use developments when developing land use ordinances.  Since most zoning regulations in the United States are developed according to Euclidean zoning principals that promote a separation of land uses, many urban planners may need to shift their mindsets. Some of the issues with using a Euclidean zoning approach include the following:

• The separation of land uses discourages walking and cycling, which fosters dependency on automobiles.
• These principles limit access to healthy foods in certain neighborhoods
• Urban plans developed using a Euclidean zoning approach actually discourages physically activity.

Cities that incorporate bicycling trails tend to have low rates of obesity. Source: NordhornerII, Wikimedia Commons

Some of the evidence-based recommendations for urban planners and zoning officials to reduce the incidence of obesity include:

• Encourage mixed-use developments with housing for both high and low-income residents
• Follow the guidelines outlined by the National Complete Streets coalition, which fosters the use of active transportation by providing safety for pedestrians and cyclists
• Develop zoning codes that promote community investment
• Ensure rigorous enforcement of zoning regulations
• Eliminate zoning that supports income inequality in the built environment
• Include zoning codes that provide for community gardens to support urban agriculture
• Provide incentives for grocers to locate stores in urban food deserts
• Preserve and provide access to open green spaces, parks, and playgrounds
• Develop and enforce tree ordinances that preserve tree canopies in order to reduce the urban heat island effect
• Encourage the construction of neighborhood schools accessible by safe walking routes to promote the use of active transportation among youth

By adhering to these guidelines, urban planners can create built environments that reduce the rates of obesity in US cities.

Do you create urban plans that encourage active lifestyles and provide access to healthy foods?