In 2016, the United Nations declared a worldwide Decade of Action on Nutrition.1 The focus of this decade is the elimination of malnutrition in all its forms, including undernutrition, micronutrient deficiencies, and overnutrition. This is a sharp departure from the historical emphasis of the United Nations agencies on the undernutrition component of the nutrition continuum. A key element of the global strategy to address malnutrition in all its forms is a food systems approach. Indeed, food systems are identified as one of six actions to promote healthy diets.1 This chapter has a twofold purpose: (1) summarize our knowledge of typologies of food systems and pathways of impact on diet quality and nutritional status and (2) analyze policies and programs that can enhance the diet quality and nutrition impacts of food systems.
A food system includes all the elements from production to consumption that influence the ability to access a healthy diet.2 In colloquial terms, a food system is farm to table, or farm to fork, or in some cases, farm to flush. The renewed emphasis on a food systems approach to improving nutritional status globally is largely driven by the overweight and obesity crisis.
There have been a variety of publications that have focused on the diet and nutrition effects of food systems3,4 in all regions and all countries. These reports have attempted, in part, to develop typologies of food systems that exist globally. There is a general consensus that food systems range from the more traditional, rural food systems to the modern, industrialized type. In the traditional food system, food is mainly produced by smallholder farmers in the immediate area, and most of the foods that are available are local and seasonal.3 For the modernized food system, a wide variety of foods are available year-round, produced from many farms, from small farms to those that are industrial in size. Production is global and therefore foods are available at any time in a modernized food system.
Each type of food system is associated with differential effects on diet and nutrition. Rural food systems are found in most developing countries, which have high rates of stunting, underweight, micronutrient deficiencies, but, until recently, low levels of overweight, obesity, and noncommunicable diseases (NCDs).3 In contrast, modern, industrialized systems, such as in the United States (U.S.), have low levels of short stature, underweight, and micronutrient deficits yet high levels of overweight, obesity, and NCDs.3 The most recent evidence, however, indicates that overweight and obesity are now increasing in all regions, even in the poorest countries of the world.5
Embedded in food systems are food value chains and food environments, both of which are critical to understanding the impact on diet quality and nutrition. A food value chain includes all the activities and actors that take ...