Association Between a Policy to Subsidize Supermarkets in Underserved Areas and Childhood Obesity Risk

Abstract

IMPORTANCEThe establishment and renovation of supermarkets may promote healthy diet practices among youth by increasing retail infrastructure for fresh foods.OBJECTIVE To estimate the association between the Food Retail Expansion to Support Health (FRESH) program and the weight status of children and adolescents.DESIGN, SETTING, AND PARTICIPANTS Using a difference-in-differences (DiD) design and including 12 months before and after a FRESH supermarket opened, data were analyzed for residentially stable public school students in kindergarten through 12th grade with objectively measured height and weight data from the academic years 2009 through 2016. Of the 8 FRESH-subsidized supermarkets in residential neighborhoods in New York City, New York, 5 were new and 3 were renovation projects between December 2011 and June 2014. Data were analyzed from June 2021 to January 2022. INTERVENTIONSThe treatment group included students who resided within 0.50 miles of a FRESH-subsidized supermarket and had at least 1 body mass index (BMI) measurement within 12 months before and 3 to 12 months after the month a FRESH supermarket opened (n = 22 712 student-year observations). A 2-stage matching-weighting approach was used to construct a control group of students who resided more than 0.50 miles from a FRESH supermarket in a FRESH-eligible area (n = 86 744 student-year observations).MAIN OUTCOMES AND MEASURES BMI z score was calculated using objectively measured height and weight data from FITNESSGRAM, an annual, school-based, standardized fitness assessment of every New York City public school student. Obesity was defined as 95th percentile or greater of the BMI z score using Centers for Disease Control and Prevention growth charts. RESULTSThe treatment group in the analytic sample had 11 356 students (22 712 student-year observations), and the control group had 43 372 students (86 744 student-year observations). The students were predominately Black (18.8%) and Hispanic and Latino (68.5%) and eligible for free or reduced-priced lunch (84.6%). There was a significant decrease in BMI z score among students who resided within 0.50 miles of a FRESH supermarket (vs control group students) in the 3-to 12-month follow-up period (DiD, −0.04; 95% CI, −0.06 to −0.02). This was true for those exposed to supermarkets that were either new (DiD, −0.07; 95% CI, −0.11 to −0.03) or renovated (DiD, −0.03; 95% CI, −0.06 to −0.01). A statistically significant decrease was also observed in the likelihood of obesity (DiD, −0.01; 95% CI, −0.02 to −0.002).CONCLUSIONS AND RELEVANCE Government-subsidized supermarkets may contribute to a small decrease in obesity risk among children residing near those supermarkets, if part of a comprehensive policy approach.

Preventing Obesity—It Is Time for Multiple Policy Strategies

“…One recent analysis of the outcomes of moving a supermarket into a low-income area, for example, reported a 1% reduction in weight-for-height among children living close to the supermarket compared with children who had more limited access. 6 Løvhaug et al 3 systematically reviewed reviews of data on single-policy interventions aimed at reducing dietary inequalities; these included not only educational policies (ie, guidelines, labeling) but also environmental policies (ie, food reformulation, marketing restrictions, price strategies, access). They judged the evidence for nearly all of these policies as too weak to evaluate effects; only soda taxes seemed to produce meaningful results.…”

Taking a Hard Look at the Empirical Evidence for Popular Community-Based Interventions in Obesity

“…There was also about a 1% greater decrease in the likelihood of obesity in the treatment group. Rummo et al conclude their report by suggesting proximity to a FRESH supermarket “may contribute to a decrease in childhood obesity risk.” But does a small (albeit statistically significant) association really suggest an important causal relationship? Indeed, Hill cautioned us to consider several aspects when considering inferring causation from association, noting that smaller associations were more plausibly due to small unknown biases than were large associations.…”

“…A policy to subsidize neighborhood supermarkets is the center of a report by Rummo et al about a New York City (NYC), New York, initiative titled Food Retail Expansion to Support Health (FRESH). Given tax and zoning incentives, FRESH supermarkets are required to have a greater proportion of their store dedicated to fresh produce and grocery products.…”

“…The authors of the current study therefore assessed whether living in proximity to a FRESH supermarket (within 0.50 miles, treatment group) was associated with likelihood of obesity and body mass index (BMI) z score change in students in kindergarten through 12th grade compared with students living further away (>0.50 miles, control group). In the student sample, BMI z score decreased to a greater degree in the treatment group than the control group.…”

“…When the affordability constraint is removed, for example, by directly providing individuals with fruits and vegetables, there is no association with body weight, despite the common recommendation that increased fruit and vegetable intake will help decrease body weight. Therefore, taken together, it seems a priori that the effectiveness of what Rummo and colleagues evaluate would be low.…”