Abstract: As illustrated by the High-Level Panel of Experts on Food Security and Nutrition of the UN Committee on World Food Security (HLPE 2017), while hunger is on the rise again, malnutrition now takes multiple forms and affects all countries.  Globally, 821 million people are still undernourished (FAO et al. 2018), over 2 billion people suffer from micronutrient deficiencies, while overweight and obesity are quickly rising which affects 1.9 billion adults and 41 million children under five.
The HLPE, in many of its publications, called for radical transformations in our current food systems to address the multiple burdens of malnutrition.  There is already enough evidence to act.  The short-term cost of action may seem high, but the cost of inaction is likely to be much higher, carrying with it a terrible legacy affecting future generations.
The HLPE (2017) identified three core elements in food systems (food supply chains, food environments and consumer behaviour, see Fig. 1).  Among these three elements, the HLPE illustrated the central role of food environments in shaping consumer behaviour and food choices and, finally, in determining diets and nutrition.
The food environment refers to the “physical, economic, political and socio-cultural context in which consumers engage with the food system to make their decisions about acquiring, preparing and consuming food” (HLPE 2017).  It consists of:
• the built environment, including: the physical food entry points (supermarkets, formal and informal markets, street kiosks, food trucks, restaurants, schools, hospitals, public canteens, etc.) where food is purchased or obtained, their location and density; the physical infrastructures that allow consumers to access these points;
• the human environment, including: the personal determinants of consumer food choices (such as income, education, values, skills, etc.); and the political, social and cultural norms that influence these choices.
The food environment is a space of convergence where all actors involved in food systems, from food producers to end consumers, interact and confront their interests, objectives and strategies.  Therefore, acting on food environments in the proper way can bring transformative changes across the whole food system for delivering healthy and sustainable diets1.  More specifically, the HLPE (2017) identified three key elements of food environments on which to act to improve the diet and nutrition outcomes of our current food systems: (i) physical and economic access to food (proximity and affordability); (ii) promotion, advertising and information; (iii) food quality and safety.  Considering these three elements and recognizing the evidence gaps in our current knowledge, the HLPE (2017) explored concretely two pathways towards more sustainable food systems2 for healthier diets:
The first pathway is to improve physical and economic access to healthy diets  This first priority adopts a food system perspective.  Food supply chains impact diets and nutrition both positively and negatively.  Governments have the key responsibility to set policies, including regulations, taxes, subsidies and other forms of incentives, which enable actors in food supply chains to maximize the nutrition value of the food produced.  Government policies and programmes which specifically focus on the food environment are also key. These include: public procurement to make diverse and healthy diets more accessible and convenient3 in public places (e.g., schools, hospitals, prisons, etc.), as well as in rural marketplaces, at reasonable prices for consumers; investments and regulations (including zoning regulations) that improve the built environment; taxing junk food or sodas; regulating product formulation; regulating nutrition and health claims on food packaging; adopting an easy to interpret front-of-the-pack labelling system; limiting advertising and promotion of unhealthy foods, especially to children and adolescents; and strengthening national food safety and quality standards, etc.
This second pathway is to strengthen consumers’ information and education on healthy diets  This second priority adopts a consumer perspective and aims at creating and strengthening the demand for heathy foods.  There is a mutual relationship between food supply chains and consumer demands.  If current food supply chains largely shape consumers’ choice, consumers can also influence food supply through their behavior and demand for specific foods.  Effective regulation, information and education have the potential to orient consumers towards healthier and more sustainable food choices.  Mass media campaigns, social and behavior change communication, social media and citizen reporting, social protection programmes and food-based dietary guidelines all serve to potentially increase awareness and influence consumer dietary choices.  Yet, information and education alone may not trigger significant changes and that communication programmes must incorporate insight on actionable steps to change habits to be more effective.   When it comes to food choices, taste, convenience, cultural norms and price often prevail over health or sustainability criteria.  The most effective way to influence demand is when healthy, palatable foods are also affordable and convenient for consumers.
In conclusion, being the interface between food supply and food demand of consumers, food environments should be privileged as the policy entry point to transform our current food systems.