Establishing healthy eating patterns early in life is critical and has implications for lifelong health. Situated interventions are a promising approach to improve eating patterns. However, HCI research has emphasized calorie control and weight loss, potentially leading consumers to prioritize caloric intake over healthy eating patterns. To support healthy eating more holistically, we designed a gameful app called Pirate Bri's Grocery Adventure (PBGA) that seeks to improve food literacy-meaning the interconnected combination of foodrelated knowledge, skills, and behaviours that empower an individual to make informed food choices-through a situated approach to grocery shopping. Findings from our three-week field study revealed that PBGA was effective for improving players' nutrition knowledge and motivation for healthier food choices and reducing their impulse purchases. Our findings highlight that nutrition apps should promote planning and shopping based on balance, variety, and moderation.

Food Literacy (FL) is associated with the improvement of autonomy and confidence around food, healthier dietary intake, and chronic disease prevention. However, to date, behaviour change research at CHI has focused on motivating healthy eating mainly through weight loss and calorie control, which can lead to poor nutritional choices as consumers optimize caloric intake over a balanced diet. To address this gap, we designed a mobile game called Pirate Bri's Grocery Adventure, that seeks to improve FL through a situated learning approach to grocery shopping. Our game leverages Self Determination Theory (SDT) to build a player's competence, autonomy, and relatedness as shoppers are encouraged to develop an understanding of the nutritional benefits of foods and are rewarded for balancing sugar, sodium, fats and fibre in their purchases.

Technology increasingly mediates our everyday interactions with food, ranging from its production and handling to the experience of preparing and eating it with friends and family. However, it is unclear whether these technologies support decisions conducive to a healthy diet. In this work, we devised the first heuristics for evaluating a technology’s support for food literacy: the interconnected combination of awareness, knowledge, and skills to empower individuals to make informed food choices. We applied an iterative, expert-driven process to derive and refine our heuristics, starting with an established food literacy framework. We then conducted evaluations with Nutrition and HCI experts to show how the heuristics support summative and formative design and evaluations of food-related technologies. We show that the heuristics are valuable design tools, and that they help participants reflect on food literacy challenges. We also discuss tensions between nutrition and HCI best practices.