Food choice decisions are challenging to conceptualise, and literature is lacking specific to adolescent food choice decisions. Understanding adolescent nutrition and food choice is becoming increasingly important. This research aims to understand what influences the food choices of Irish adolescents, and the mental negotiations occurring in food-based decisions. Additionally, it aims to develop a holistic conceptual model of food choice, specific to adolescents. A qualitative study was conducted in N = 47 Irish adolescents, via focus group discussions using vignettes to introduce discussion topics around food and eating habits. Data were analysed using reflexive thematic analysis, involving both semantic and latent analysis. Thirteen distinct factors related to adolescent food choices were discussed, forming one main theme and three inter-linking subthemes. The main theme relates to food choice being multi-factorial in nature, needing a balance of priorities through internal negotiations for food choice with the aim of reducing food guilt. This can change depending on the social setting. Social concerns and food guilt appear to play a strong role in adolescent food choice, with adolescents feeling guilty for eating unhealthy food, wasting food, or spending/wasting money on food. A conceptual model for food choice in adolescents was developed, named a “Food Choice Funnel”, incorporating a specific “Food Guilt Matrix”. While we should encourage healthy eating and a healthy lifestyle, it is important to understand the value placed on the social component to eating among adolescents, since they have increasing social interactions and occasions where choosing health-promoting foods may be more challenging. Healthy eating messages should be designed in a balanced manner to support healthy growth and development, while limiting the potential to induce feelings of guilt among adolescents.