Food environment and diabetes mellitus in South Asia: A geospatial analysis of health outcome data

Abstract

Background The global epidemic of type 2 diabetes mellitus (T2DM) renders its prevention a major public health priority. A key risk factor of diabetes is obesity and poor diets. Food environments have been found to influence people’s diets and obesity, positing they may play a role in the prevalence of diabetes. Yet, there is scant evidence on the role they may play in the context of low- and middle-income countries (LMICs). We examined the associations of food environments on T2DM among adults and its heterogeneity by income and sex. Methods and findings We linked individual health outcome data of 12,167 individuals from a network of health surveillance sites (the South Asia Biobank) to the density and proximity of food outlets geolocated around their homes from environment mapping survey data collected between 2018 and 2020 in Bangladesh and Sri Lanka. Density was defined as share of food outlets within 300 m from study participant’s home, and proximity was defined as having at least 1 outlet within 100 m from home. The outcome variables include fasting blood glucose level, high blood glucose, and self-reported diagnosed diabetes. Control variables included demographics, socioeconomic status (SES), health status, healthcare utilization, and physical activities. Data were analyzed in ArcMap 10.3 and STATA 15.1. A higher share of fast-food restaurants (FFR) was associated with a 9.21 mg/dl blood glucose increase (95% CI: 0.17, 18.24; p Conclusions Our results suggest that the exposure to fast-food outlets may have a detrimental impact on the risk of T2DM, especially among females and higher-income earners. Policies should target changes in the food environments to promote better diets and prevent T2DM. Dian Kusuma and colleagues investigate the associations between exposure to the density and proximity of healthy and unhealthy food outlets and diabetes in Bangladesh and Sri Lanka. Author summary Why was this study done? With a global prevalence of 9% (463 million people) in 2019, the widespread epidemic of diabetes mellitus renders the prevention of this condition a major priority for public health. Creating health-enabling environments that promote healthy eating and physical activity is needed to reduce the number of people suffering from diabetes. Food environments influence risk factors for type 2 diabetes mellitus (T2DM), but this evidence is understudied among low- and middle-income countries (LMICs). What did the researchers do and find? We examined the associations between the exposure to the density and proximity of healthy and unhealthy food outlets and diabetes (i.e., fasting blood glucose level, high blood glucose, and diagnosed diabetes) using the South Asia Biobank and environment mapping data for 12,167 adults collected between 2018 and 2020 for Bangladesh and Sri Lanka. We found that a higher share of fast-food outlets was associated with a 9.21 mg/dl blood glucose increase. Also, a 1% increase in the share of fast-food outlets was associated with an 8% increase in the probability of being diagnosed with diabetes. Having at least 1 fast-food retailer in the proximity of one’s home was associated with 2.14 mg/dl blood glucose increase. While the association between the density of fast-food retailers and blood glucose level was stronger among women than men, density of fast-food restaurants (FFRs) increased the likelihood of being diagnosed with diabetes for both men and women. The association between proximity to these outlets and blood glucose level was stronger among men. Both density and proximity of fast-food outlets were associated with diabetes outcomes among high-income earners. Density of FFRs was associated with increased probability of being diagnosed with diabetes for low-income earners, although the effect size was smaller than for high-income earners. What do these findings mean? The exposure to fast-food outlets may have a detrimental impact on the risk of diabetes, especially among females and those with higher income. Policies should target changes in the food environments to promote better diets and prevent diabetes.