Neighborhood - A Risk Factor for Diabetes

November is Diabetes Awareness Month

According to the CDC, in 2011 18.8 million people were living with diagnosed diabetes while an additional 7 million people had diabetes that went undiagnosed. Roughly 1 of every 3 Americans are at high risk of developing type 2 diabetes. The risk factors for type 2 diabetes include:

·       Being 45 or older

·       Having a family history of diabetes

·       Being overweight

·       Not exercising regularly

·       Having high blood pressure

·       Having low HDL, also known as "good" cholesterol and/or high levels of triglycerides

·       Certain racial and ethnic groups (e.g., Non-Hispanic Blacks, Hispanic/Latino Americans, Asian Americans and Pacific Islanders, and American Indians and Alaska Native.)

One large factor that isn’t explicitly mentioned is neighborhood - poor neighborhoods tend to have high diabetes prevalence among residents compared to higher income neighborhoods. In New York City, the diabetes-related mortality rate was 2.7 times higher among individuals in high-poverty neighborhoods than in low-poverty neighborhoods. One in seven residents in South Los Angeles has diabetes, compared to one in 12 in West Los Angeles. Forty-two percent of South L.A. residents live below the federal poverty level, compared to twelve percent in West Los Angeles.

There is a clear gradient between diabetes diagnosis and income. The graph below is from the CDC and shows that as income level increases, the percent of people diagnosed with diabetes decreases.

Before we address why diabetes is more common in poor neighborhoods, we need to differentiate between the two types of diabetes. Below is a simplified overview.

Type 1 diabetes

• Roughly 5% of diagnosed diabetes
• Usually first diagnosed as children
• Risk factors are largely genetic or autoimmune and not preventable

Type 2 diabetes

• Roughly 95% of diagnosed diabetes
• Mainly associated with lifestyle and preventable

While type 1 diabetes is a serious condition, note that most of what I am writing about pertains to type 2 diabetes.

There are several reasons why diabetes prevalence is higher in poor neighborhoods and among lower income families. I will focus on two of the most important reasons.

1. Association between food deserts and diabetes. According to the CDC, food deserts are “Areas that lack access to affordable fruits, vegetables, whole grains, low-fat milk, and other foods that make up a full and healthy diet.” Food deserts exist in areas that lack large grocery stores but have small convenience stores and fast food options. Many low-income, minority, and rural neighborhoods are considered food deserts. Food deserts are environmental constructs and a result of centuries of social and business politics. There are many reasons why people live in food deserts - racial housing practices, the high cost of housing in other areas of a city, family history, transportation, etc.  It is not surprising that high-food desert counties had rates of adult diabetes that are five times higher than counties with enough grocery stores. Above is a food pyramid emphasizing the importance of fruits, grains, and vegetables in the diet. For people who live in neighborhoods that lack access to healthy foods, diet is not a personal choice, as they must rely on heavily processed foods that are available. 
2. Association between neighborhood walkability and diabetes. Researchers in Toronto found that people who live in less walkable neighborhoods are significantly more likely to develop diabetes.  This makes sense since one of the risk factors for diabetes is limited physical activity. Walkable communities ‘trick’ people into physical activity since they can walk rather than drive to the bus stop, to school, and to stores. Although many poorer neighborhoods might be considered walkable based on density and mixed use developments, poor neighborhoods have fewer street trees, clean streets, and sidewalk cafes, and higher rates of felony complaints, narcotics arrests, and vehicular crashes. Basically, if residents do not feel safe, they will not walk. Walking is a great form of physical activity. It is cheap and doesn’t take equipment but it isn’t so easy for someone in many low-income neighborhoods to go for a walk.

So, would moving people into higher income neighborhoods decrease their likelihood of diabetes? Maybe! Researchers looked at a group of mothers who were moved from high to low poverty areas. A decade later, they report that rates of diabetes and severe obesity are about one-fifth lower in the women who moved than in those who did not.

Type 2 diabetes is a highly preventable and controllable disease. However, for millions of Americans living in poor neighborhoods, type 2 diabetes is not preventable. To decrease rates of diabetes, the first step is to recognize the link between income and diabetes. The next step is to stop universally considering type 2 diabetes a preventable disease. Stop blaming the person or family and start looking at the environment. In many cases, the solution is not simply to tell someone to walk more and modify his diet. The solution is much more challenging. The solution is to create policies that improve poor neighborhoods that have been ignored for so long with access to fresh foods and safe streets.