Madhumita Ghosh-Dastidar

Diet And Perceptions Change With Supermarket Introduction In A Food Desert, But Not Because Of Supermarket Use

Placing full-service supermarkets in food deserts--areas with limited access to healthy food--has been promoted as a way to reduce inequalities in access to healthy food, improve diet, and reduce the risk of obesity. However, previous studies provide scant evidence of such impacts. We surveyed households in two Pittsburgh, Pennsylvania, neighborhoods in 2011 and 2014, one of which received a new supermarket in 2013. Comparing trends in the two neighborhoods, we obtained evidence of multiple positive impacts from new supermarket placement. In the new supermarket neighborhood we found net positive changes in overall dietary quality; average daily intakes of kilocalories and added sugars; and percentage of kilocalories from solid fats, added sugars, and alcohol. However, the only positive outcome in the recipient neighborhood specifically associated with regular use of the new supermarket was improved perceived access to healthy food. We did not observe differential improvement between the neighborhoods in fruit and vegetable intake, whole grain consumption, or body mass index. Incentivizing supermarkets to locate in food deserts is appropriate. However, efforts should proceed with caution, until the mechanisms by which the stores affect diet and their ability to influence weight status are better understood.

The Women's Health Initiative: The food environment, neighborhood socioeconomic status, BMI, and blood pressure.

Using data (n = 60,775 women) from the Womens Health Initiative Clinical Trial (WHI CT)—a national study of postmenopausal women aged 50–79 years—we analyzed cross‐sectional associations between the availability of different types of food outlets in the 1.5 miles surrounding a womans residence, census tract neighborhood socioeconomic status (NSES), BMI, and blood pressure (BP). We simultaneously modeled NSES and food outlets using linear and logistic regression models, adjusting for multiple sociodemographic factors, population density and random effects at the tract and metropolitan statistical area (MSA) level. We found significant associations between NSES, availability of food outlets and individual‐level measurements of BMI and BP. As grocery store/supermarket availability increased from the 10th to the 90th percentile of its distribution, controlling for confounders, BMI was lower by 0.30 kg/m2. Conversely, as fast‐food outlet availability increased from the 10th to the 90th percentile, BMI was higher by 0.28 kg/m2. When NSES increased from the 10th to the 90th percentile of its distribution, BMI was lower by 1.26 kg/m2. As NSES increased from the 10th to the 90th percentile, systolic and diastolic BP were lower by 1.11 mm Hg and 0.40 mm Hg, respectively. As grocery store/supermarket outlet availability increased from the 10th and 90th percentiles, diastolic BP was lower by 0.31 mm Hg. In this national sample of postmenopausal women, we found important independent associations between the food and socioeconomic environments and BMI and BP. These findings suggest that changes in the neighborhood environment may contribute to efforts to control obesity and hypertension.

Does Opening a Supermarket in a Food Desert Change the Food Environment

Abstract Improving access to healthy foods in low‐income neighborhoods is a national priority. Our study evaluated the impact of opening a supermarket in a ‘food desert’ on healthy food access, availability and prices in the local food environment. We conducted 30 comprehensive in‐store audits collecting information on healthy and unhealthy food availability, food prices and store environment, as well as 746 household surveys in two low‐income neighborhoods before and after one of the two neighborhoods received a new supermarket. We found positive and negative changes in food availability, and an even greater influence on food prices in neighborhood stores. The supermarket opening in a ‘food desert’ caused little improvement in net availability of healthy foods, challenging the underpinnings of policies such as the Healthy Food Financing Initiative. HighlightsOur study evaluated the impact of opening a supermarket in a ‘food desert’ designed to reduce inequities in healthy food access.While the supermarket opening resulted in significant improvements in geographic access to a supermarket for intervention neighborhood residents, we did not see a reduction of similar magnitude in distance to regular place of food shopping.Contrary to expectation, the introduction of a supermarket did not result in healthy food availability more than is likely to have happened naturally, in the absence of government intervention.The new supermarket may have also inhibited increases in availability in other intervention neighborhood stores, relative to the control neighborhood – with a larger decline in fruit and vegetable availability than junk food availability.When looking at changes in food price in the intervention neighborhood, we saw a decrease in staple prices but a sharp increase in junk food prices.Findings suggest that local food system responses to environmental change are complex and dynamic and careful description of local environmental changes related to diet as a result of supermarket interventions is therefore needed in any future study.

Where do food desert residents buy most of their junk food? Supermarkets.

OBJECTIVE To examine where residents in an area with limited access to healthy foods (an urban food desert) purchased healthier and less healthy foods. DESIGN Food shopping receipts were collected over a one-week period in 2013. These were analysed to describe where residents shopped for food and what types of food they bought. SETTING Two low-income, predominantly African-American neighbourhoods with limited access to healthy foods in Pittsburgh, PA, USA. SUBJECTS Two hundred and ninety-three households in which the primary food shoppers were predominantly female (77·8 %) and non-Hispanic black (91·1 %) adults. RESULTS Full-service supermarkets were by far the most common food retail outlet from which food receipts were returned and accounted for a much larger proportion (57·4 %) of food and beverage expenditures, both healthy and unhealthy, than other food retail outlets. Although patronized less frequently, convenience stores were notable purveyors of unhealthy foods. CONCLUSIONS Findings highlight the need to implement policies that can help to decrease unhealthy food purchases in full-service supermarkets and convenience stores and increase healthy food purchases in convenience stores.

Are our actions aligned with our evidence? The skinny on changing the landscape of obesity.

Recent debate about the role of food deserts in the United States (i.e., places that lack access to healthy foods) has prompted discussion on policies being enacted, including efforts that encourage the placement of full‐service supermarkets into food deserts. Other initiatives to address obesogenic neighborhood features include land use zoning and parks renovations. Yet, there is little evidence to demonstrate that such policies effect change. While we suspect most researchers and policymakers would agree that effective neighborhood change could be a powerful tool in combating obesity, we desperately need strong and sound evidence to guide decisions about where and how to invest.

Does where you shop or who you are predict what you eat?: The role of stores and individual characteristics in dietary intake

Interventions to address diet, a modifiable risk factor for diabetes, cancer, and cardiovascular disease, have increasingly emphasized the influence of the physical environment on diet, while more traditional approaches have focused on individual characteristics. We examined environmental and individual influences on diet to understand the role of both. Household interviews were conducted in 2011 with 1372 individuals randomly selected from two low-income, predominantly African American neighborhoods in Pittsburgh, PA. Participants reported their sociodemographic characteristics, food shopping behavior, and dietary intake. Both food shopping frequency at different types of food stores and sociodemographic characteristics showed significant associations with diet in adjusted regression models. More frequent shopping at convenience and neighborhood stores and being younger, male, without a college degree, and receiving SNAP benefits were associated with greater intake of sugar-sweetened beverages (SSBs), added sugars, and discretionary fats. Being older, male, and having a college degree were associated with greater intake of fruits and vegetables. However, while food shopping behavior and sociodemographic characteristics accounted for similar amounts of nonoverlapping variance in fruit and vegetable intake, food shopping behavior accounted for much less variance, and little unique variance, in SSBs, added sugars, and discretionary fats in models with sociodemographic characteristics. The current study reinforces the need for policies and interventions at both the environmental and individual levels to improve diet in food desert residents. Individual interventions to address food choices associated with certain sociodemographic characteristics might be particularly important for curbing intake of SSBs, added sugars, and discretionary fats.

Food policy research: we need better measurement, better study designs, and reasonable and measured actions based on the available evidence.

To the Editor: Lucan and Chambers, in their Letter to the Editor, call for better measurement in order to move food-environment research forward. We wholeheartedly agree. In fact, this issue is not new to the obesity policy agenda1. However, attaining validated and detailed food environment data in a large-scale (e.g., national) setting is prohibitively costly. Our study included 68,132 women living in in 18,186 census tracts across the United States2. We excluded women who lived in census tracts with a population count of less than 500 and women living outside metropolitan statistical areas because we believed measures of the food environment would not be comparable in urban and rural areas. As we pointed out in our paper, most studies to date have analyzed a single type of food outlet (e.g., grocery stores or fast-food outlets) at one time. We examined multiple dimensions of the food environment in a national dataset – and believe that these data and analyses bring the state of the literature forward. We concur that detailed ground observations, such as the ones Lucan and Chambers reference, are ideal. However, these can only be executed in confined geographic settings. Such data would be extremely difficult, if not impossible, to attain on a national scale. We also agree with Lucan and Chambers’ concerns with 1) assumptions that establishments categorized as full-service supermarkets are all comparable; 2) potentially relevant food sources such as farmers’ markets and mobile produce stands may not be captured through commercial database listings; and 3) using radial buffers and proximity to a store to capture access without capturing factors such as transportation mode, travel time and social norms around food purchasing. Such detailed evidence can complement and validate studies based on large national data to ensure that policies are based on a solid scientific foundation. Importantly, we are working on that. Members of our team are involved with the largest study to date in the United States that is capitalizing on a natural experiment of the elimination of a food desert (1R01CA149105, Does a New Supermarket Improve Dietary Behaviors of Low-income African Americans?). Examination of a natural experiment of this type (i.e., elimination of a food desert) is allowing our team to overcome many of these limitations, from reliance on unvalidated commercial databases (we are conducting food audits to collect price, quality and availability of food data from all food purchasing venues in residential neighborhoods included in our study as well as the most frequently report venues our enrolled population reports shopping), to a longitudinal quasi-experimental study design with a control or comparison neighborhood, and extensive data on residents’ dietary intake, travel mode, time spent in shopping, and experience of food purchasing. We have just completed our baseline data collection and hope that findings from this study when completed will be replicable to other low-income African American neighborhoods across the United States. However, we are indeed confined to one large natural experiment and unlike our published study, will not be analyzing data based on tens of thousands of individuals and census tracts. We agree that the field faces measurement limitations. Large observational studies, such as the one our paper reported, have imperfect measures. However, given the considerable impact of nutrition on obesity and other health problems, we believe that reasonable and measured actions based on the available evidence need to be considered. Policy makers cannot afford to rely solely on data from detailed studies of a few neighborhoods (one could argue a requirement for grounding approaches) and need to know whether results hold at a national level. Our study does that, and the methods we used are necessary to such a study. Although we agree that the field also needs studies of small areas with rich and detailed measures to complement the national data and help us determine their validity, we still conclude that our findings support restricting the development of fast-food outlets and attracting grocery stores, and are committed to additional research that overcomes the limitations of large studies such as the one we published.

Attitudes and Barriers to Healthy Diet and Physical Activity: A Latent Profile Analysis:

Healthy diet and physical activity (PA) prevent and reduce chronic disease. Social cognitive theory delineates multiple attitudes and barriers that influence these behaviors. Understanding covariation in these attitudes and barriers is complex. We examined whether individuals could be grouped into a small number of categories that are easier to study. Interviews were conducted with 982 adults from two low-income, predominantly African American neighborhoods in the same city. Social cognitive constructs, including self-efficacy, social norms, and internal and external barriers to diet and exercise, and walking were self-reported. We measured moderate to vigorous physical activity with accelerometers and diet with 24-hour recalls. We conducted a latent profile analysis of attitudes and barriers to diet and PA and identified four classes: (a) moderate diet and negative exercise attitudes, where participants were roughly average on dietary attitudes but reported exercise-related challenges, including lower social support, outcome expectancies, physical functioning, and self-efficacy; (b) few barriers and benefits of healthy diet and exercise, where participants reported fewer barriers and lower outcome expectancies for diet and PA; (c) moderate overall attitudes, where participants had average scores on most indicators but below-average exercise self-efficacy and slightly more exercise barriers; and (d) positive overall attitudes, characterized by more positive attitudes toward both diet and PA across most domains, particularly regarding self-efficacy to overcome exercise barriers. These profiles could inform efforts to tailor individual-level interventions for diet and PA of persons at high risk of chronic diseases.

The power of social networks and social support in promotion of physical activity and body mass index among African American adults

Social support and social networks can elucidate important structural and functional aspects of social relationships that are associated with health-promoting behaviors, including Physical Activity (PA) and weight. A growing number of studies have investigated the relationship between social support, social networks, PA and obesity specifically among African Americans; however, the evidence is mixed and many studies focus exclusively on African American women. Most studies have also focused on either functional or structural aspects of social relationships (but not both) and few have objectively measured moderate-to-vigorous physical activity (MVPA) and body mass index (BMI). Cross-sectional surveys of adult African American men and women living in two low-income predominantly African American neighborhoods in Pittsburgh, PA (N = 799) measured numerous structural features as well as functional aspects of social relationships. Specifically, structural features included social isolation, and social network size and diversity. Functional aspects included perceptions of social support for physical activity from the social network in general as well as from family and friends specifically. Height, weight, and PA were objectively measured. From these, we derived Body Mass Index (BMI) and moderate-to-vigorous physical activity (MVPA). All regression models were stratified by gender, and included age, income, education, employment, marital status, physical limitations, and a neighborhood indicator. Greater social isolation was a significant predictor of lower BMI among men only. Among women only, social isolation was significantly associated with increased MVPA whereas, network diversity was significantly associated with reduced MVPA. Future research would benefit from in-depth qualitative investigations to understand how social networks may act to influence different types of physical activity among African Americans, as well as understand how they can be possible levers for health promotion and prevention.

Improved parental dietary quality is associated with children’s dietary intake through the home environment

Improving access to supermarkets has been shown to improve some dietary outcomes, yet there is little evidence for such effects on children. Relatedly, there is a dearth of research assessing the impact of a structural change (i.e. supermarket in a former food desert) on the home environment and its relationship with childrens diet.