Gina Kolata, writing for the New York Times, has sparked some debate with this article: "Studies Question the Pairing of Food Deserts and Obesity". In general I often wish that science reporting focused more on how the new studies fit in with the old, rather than just the (exciting) new ones. On first reading I noticed that one study is described as having explored the association of "the type of food within a mile and a half of their homes" with what people eat. This raised a little question mark in my mind, as I know that prior studies have often looked at distances much shorter than 1.5 miles, but it was mostly a vague hesitation. And if you didn't know that before reading the article, then you've missed a major difference between the old and new results (and one that could have been easily explained). Also, describing something as "an article of faith" when it's arguably something more like "the broad conclusion draw from most most prior research"... that certainly established an editorial tone from the beginning.
Intrigued, I sent the piece to a friend (and former public health classmate) who has work on food deserts, to get a more informed reaction. I'm sharing her thoughts here (with permission) because this is an area of research that I don't follow as closely, and her reactions helped me to situate this story in the broader literature:
1. This quote from the article is so good!
"It is always easy to advocate for more grocery stores,” said Kelly D. Brownell, director of Yale University’s Rudd Center for Food Policy and Obesity, who was not involved in the studies. “But if you are looking for what you hope will change obesity, healthy food access is probably just wishful thinking.”
The "unhealthy food environment" has a much bigger impact on diet than the "healthy food environment", but it's politically more viable to work from an advocacy standpoint than a regulatory standpoint. (On that point, you still have to worry about what food is available - you can't just take out small businesses in impoverished neighborhoods and not replace it with anything.)
2. The article is too eager to dismiss the health-food access relationship. There's good research out there, but there's constant difficulty with tightening methods/definitions and deciding what to control for. The thing that I think is really powerful about the "food desert" discourse is that it opens doors to talk about race, poverty, community, culture, and more. At the end of the day, grocery stores are good for low-income areas because they bring in money and raise property values. If the literature isn't perfect on health effects, I'm still willing to advocate for them.
3. I want to know more about the geography of the study that found that low-income areas had more grocery stores than high-income areas. Were they a mix of urban, peri-urban, and rural areas? Because that's a whole other bear. (Non-shocker shocker: rural areas have food deserts... rural poverty is still a problem!)
4. The article does a good job of pointing to how difficult it is to study this. Hopkins (and the Baltimore Food Czar) are doing some work with healthy food access scores for neighborhoods. This would take into account how many healthy food options there are (supermarkets, farmers' markets, arabers, tiendas) and how many unhealthy food options there are (fast food, carry out, corner stores).
5. The studies they cite are with kids, but the relationship between food insecurity (which is different, but related to food access) and obesity is only well-established among women. (This, itself, is not talked about enough.) The thinking is that kids are often "shielded" from the effects of food insecurity by their mothers, who eat a yo-yo diet depending on the amount of food in the house.
My friend also suggested the following articles for additional reading:
- Food deserts are complex and real (Amanda Behrens, Center for a Livable Future)
- Baltimore food czar: food deserts studies don't apply (Adam Bednar, North Baltimore Patch)
- Nischan, Nestle Weigh In On Food Deserts (Eleanor West, Food Republic)