Abstract
Food consumption has two main impacts: (1) on the human health through nutrition, and (2) on the whole environment through the life cycle of products. From a policy perspective, favoring the consumption of healthy and environmental-friendly products is both a major public health issue and one important lever to address climate change. However, consumers only have limited information per se about the true qualities of a given food product, which may hamper their ability to decide on what they can safely eat or stop eating. A primary way of informing consumers about their food purchases is the use of labels, and especially 5-colors labels (from A to E) whose effectiveness has been scientifically documented. In Europe, and particularly in France, the NutriScore has been adopted as the main tool to inform consumers about the nutritional quality of products or meals. As for the environmental impact of goods, the Ecoscore is emerging as a potentially effective candidate.
There exists a large literature on the impact of nutritional labels, and in particular the NutriScore, on consumers' food quality intake as well as a growing literature focusing on the effects of environmental labelling (such as the EcoScore). However, studying the combination of both types of labels is relatively new. At the same time, that labels may enable to achieve the reduction in consumption of both unhealthy and environmentally-damaging products is debatable. Moreover, product information is only one dimension of the food decision, which is also heavily dependant on the broad choice architecture, and particularly on the way products are presented to consumers. In physical food purchases (online shop, supermarket, recipe book, etc.), products are organised by categories, price families, or other rankings that are decided by sellers. In web or mobile apps, which are increasingly used in daily food decisions, products are often ranked by popularity or by grades provided by past customers (e.g: restaurants). Selective ranking of products, which is a type of “nudge”, has indeed been documented as a powerful lever for behavioral change. If it was be possible to rank the products, meals or recipes by their NutriScore or their EcoScore (from A to E, from green to red), what would be the impact on the nutritional and environmental quality of food choices ?
To answer this question, we build a field experiment based on naturally-occuring food decisions using a mobile phone application which offers users the possibility to search for recipes that fit their needs and habits. We partner with the private firm that owns the application to exogenously manipulate the ranking of proposed recipes given users' inputs. Through randomization into treatments and observation of all users in a pre-intervention phase (with ranking by recipes' grades as baseline), we are able to assess the ceteris paribus effect of ranking recipes based on either the NutriScore or the EcoScore on both the nutritional and environmental quality of selected recipes.