Africa's Changing Food Environments and Nutritional Effects on Adults and Children.

Many low- and middle-income countries (LMICs) are experiencing profound changes in food environments, including a rapid growth of supermarkets and other modern retailers. Changing food environments can influence people's diets, nutrition, and health. While in many LMICs, undernutrition and micronutrient deficiencies are still widespread, problems of overweight, obesity, and related non-communicable diseases are also massively on the rise. Supermarkets seem to contribute to overweight and obesity among adults, but effects on children and adolescents could possibly be different. Here, we review the available evidence about the implications of supermarkets for people's diets, nutrition, and health. Particular emphasis is placed on recent studies from urban Kenya that used panel data and differencing techniques to identify causal effects on different age cohorts. The results from Kenya show that shopping in supermarkets contributes to higher consumption of processed and highly processed foods and lower consumption of unprocessed foods. These dietary changes lead to significant increases in the body mass index and the probability of being overweight/obese and pre-diabetic among adults. For children, the same increases in overweight are not observed. Instead, supermarket shopping increases child height-for-age Z-scores. Despite higher food processing levels, supermarkets enhance food variety and dietary diversity in the relatively poor households. The results confirm that the growth of supermarkets affects adult and child nutrition differently; while the effects on adults are negative, the effects on children are positive, especially in the Kenyan context where child undernutrition is still widespread. Better understanding the effects of changing food environments on different age cohorts and in different contexts is important to design strategies that can help to make food choices in LMICs healthier. More research in different geographical settings will be useful.