The High Level Panel of Experts on Food and Nutrition Security defines in its report on “ Nutrition and food systems ” that food systems gather “...all the elements (environment, people, inputs, processes, infrastructures, institutions, etc.) and activities that relate to the production, processing, distribution, preparation and consumption of food, and the output of these activities, including socio-economic and environmental outcomes.” (HLPE, 2017b).

Food systems are therefore characterized by complex interactions between food system actors and feedback loops between food system processes. Food systems are very diverse and range from traditional systems involving few people and short supply chains, over mixed to modern food systems, made of a complex webs of a large number of actors and processes that grow, transform food commodities into food products and distribute them globally (Gómez and Ricketts, 2013; HLPE, 2017a).

The food environment plays an important role for the food choices and diets of people. Food environments consist of the “physical, economic, political and socio-cultural context in which consumers engage with the food system to acquire, prepare and consume food” (HLPE, 2017a). In many food systems, the food processing, retail and service sectors are also influencing the options of primary producers and farmers to market their products.

Sustainable food systems contribute to global food security and nutrition in all its dimensions. They are regarded to encompass all pillars of sustainability to deliver the following:

1. Access to safe and nutritious food for all;
2. Sustainable healthy diets;
3. Climate and nature-positive production system (sustainable use of resources, minimizing environmental pollution, maintaining or increasing biodiversity);
4. Equitable livelihoods for all food system actors and fair value distribution;
5. Resilience to vulnerabilities, shocks and stresses

“Sustainable healthy Diets are dietary patterns that promote all dimensions of individuals’ health and wellbeing; have low environmental pressure and impact; are accessible, affordable, safe and equitable; and are culturally acceptable” (FAO and WHO, 2019).

Today, food systems are largely failing to deliver on these objectives. Large inequalities exist on all dimensions both within and across countries. Globally, about 2 billion people are affected by moderate or severe food insecurity (FAO et al., 2020), while more than 2 billion were overweight (FAO et al., 2019). The global food system contributes about one third of total anthropogenic GHG emissions (Crippa et al., no date; Rosenzweig et al., 2020), is contributing significantly to the exceedance of several planetary boundaries (Rockström et al., 2020), while child labor, unfair trading practices and inhumane working conditions prevail in many value chains. Adding to the problem, around one-third of all food produced globally is lost or wasted (FAO).

The transformation of the current towards sustainable food systems is therefore urgently needed. Several countries and regions have recognized this need as being of high priority, such as the European Union. With its Farm to Fork strategy, an important element of Europe’s Green Deal, the EU has laid down an ambitious agenda towards sustainable food systems. A legislative framework supporting the implementation of the strategy and the development of sustainable food policy will be put in place. At global level, the EU will support the transition to sustainable agri-food systems through its trade policies and international cooperation instruments.

Agroecology, by applying ecological principles to agriculture and ensuring a regenerative use of natural resources and ecosystem services while also addressing the need for socially equitable food systems (HPLE, 2019) is increasingly promoted as being able to contribute to transforming food systems.

Similarly, fisheries and aquaculture are seen as a lower footprint production source (compared to agriculture) contributinge to global food security and sustainability. Per kilogram of output and compared to livestock production, aquatic animal production systems have a lower carbon footprint and emission of nitrogen and phosphorous are much lower. In addition, the consumption of fish, shellfish and algae contributes to the transition to a healthy and sustainable diet.

In developing countries, sustainable, safe and resilient food systems are needed to achieve food and nutrition security and boost economic development, in particular by realizing the full potential of free trade agreements.

To raise global awareness on the urgency of food system transformation, and foster commitments for concrete actions, the UN Secretary-General António Guterres has decided to convene a Food Systems Summit in 2021 .