Vegetables for Healthy Diets in Low- and Middle-Income Countries: A Scoping Review of the Food Systems Literature

Background: Vegetables are an essential element in healthy diets, but intakes are low around the world and there is a lack of systematic knowledge on how to improve diets through food system approaches. Methods: This scoping review assessed how studies of food systems for healthy diets have addressed the role of vegetables in low- and middle-income countries. We apply the PRISMA guidelines for scoping reviews to narratively map the literature to an accepted food systems framework and identify research gaps. Results: We found 1383 relevant articles, with increasing numbers over 20 years. Only 6% of articles looked at low-income countries, and 93% looked at single-country contexts. Over half of articles assessed vegetables as a food group, without looking at diversity within the food group. 15% looked at traditional vegetables. Issues of physical access to food were among the least studied food system topics in our review (7% of articles). Only 15% of articles used a comprehensive food system lens across multiple dimensions. There is also a research gap on the impacts of different policy and practice interventions (13% of articles) to enable greater vegetable consumption. Conclusions: Food system studies necessarily drew on multiple disciplines, methods and metrics to describe, analyze, and diagnose parts of the system. More work is needed across disciplines, across contexts, and across the food system, including understanding interventions and trade-offs, and impacts and change for diets particularly of marginalized population groups. Filling these gaps in knowledge is necessary in order to work toward healthy vegetable-rich diets for everyone everywhere.