This article is more than 5 years old. Information may no longer be current.

Relationship between obesity and food environment questioned

There is “no robust” relationship between obesity and the types of food available in a neighborhood, according to recent study results.

Although policymakers and federal organizations such as the White House Childhood Obesity Task Force and the CDC have argued that improved access to supermarkets and reduced access to fast food restaurants and convenient stores are an important step to combat childhood obesity, RAND Corporation researchers Ruopeng An, MPP, and Roland Strum, PhD, found little evidence to support that type of intervention.

“Recently, the notion of a ‘food desert’ is widely cited in media and in shaping public health policies, despite the mixed results from previous studies,” An told Healio.com. “We thus decided to use a large state representative survey data with precise geographical information for survey participants to test the ‘food desert’ hypothesis.”

The researchers analyzed survey data on the self-reported heights, weights and diets of 8,226 children aged 5 to 11 years and 5,236 adolescents aged 12 to 17 years. Participants were sampled from the 2005 and 2007 California Health Interview Surveys.

Using a geospatial processing program, the researchers measured neighborhood food environments by drawing buffers with four separate radii (0.1, 0.5, 1 and 1.5 miles) centered on participants’ residences and schools. After locating food outlets such as fast food restaurants, convenience stores, midsize grocery stores and large supermarkets, the researchers layered those store locations over the buffers to create a picture of available food locations within participants’ walking distance.

Results showed that adolescents consumed more soda, fast food and sugar compared with children. The researchers found no evidence to support the hypothesis that greater availability of fast food restaurants or limited access to supermarkets within walking distance affected diet and obesity among children and adolescents.

“We were able to demonstrate that across many different measures of the neighborhood environment and using a large state representative data, there was no robust relationship between the food environment and a youth’s diet or obesity,” An said. “There are some isolated effects, but most probably due to chance.”

Since the relationship between neighborhood food environments and diet is questionable, An recommended other potential interventions that may be effective in combating childhood obesity:

• Free fruits and vegetables at school.
• Provision of low-calorie snacks and beverages in the school vending machines at reduced prices.
• Provision of vouchers or price discounts for parents to purchase healthy foods in supermarkets or grocery stores.
• Promotion of farmers’ markets in deprived neighborhoods.
• Impose noticeable taxes on unhealthy foods high in fat, sugar or salt, and use revenues generated from those “fat taxes” to subsidize healthy food purchases, such as produce.

“Those economic incentives might play a more important role than education campaign or food labeling,” An said, “and there is also evidence that a combination of those strategies may provide better outcomes.”