Ultra-processed food consumption in New Zealand adolescents: the role of eating context

Adolescence represents a critical window in development, marked by rapid growth and the formation of eating habits and preferences. Understanding how adolescent food choices are shaped is fundamental to encouraging healthy diets. This study is the first to explore associations between eating contexts and ultra-processed food (UPF) consumption and its contribution to energy intake by meal occasion among New Zealand (NZ) adolescents. A secondary objective examined associations between where foods were sourced and UPF intake. Dietary intake was assessed via a 24-hour food recall, using the web-based technology Intake24 from a convenience sample of adolescents (n=631), aged 12-17, from schools within the Auckland, Bay of Plenty and Waikato regions in NZ. Foods were categorised into their level of processing using the NOVA classification system (1) . Eating context was assessed by location consumed, with whom and whether an electronic device was present, across six mealtimes. Frequent eating patterns, classed as social dyads (where and with whom), were identified. Linear regression models were used to analyse the association between contextual factors and UPF intake in SPSS v.29.0.UPF contributed 62.5% (SD 25.3) of total daily energy intake overall. Intake was significantly higher at snack times, particularly evening snacks, where UPF accounted for 79.6% (SD 34.5) of energy intake at that occasion (P < 0.05). Meals consumed on the go (81.4%, SD 31.7), in bedrooms (73.7%, SD 36.5), and eaten at fast-food outlets (74.0%, SD 38.7) had the highest UPF contributions by location. Parental presence, especially at the family table, was protective (51.3%, SD 39.5), whereas UPF intake was significantly higher when eating meals alone (65.6%, SD 38.6), with friends (66.2%, SD 37.8), or with others (80.0%, SD 30.1) (P < 0.05). Food sourced from convenience stores and fast-food outlets contributed more than 80% UPF, whereas school lunch programmes contributed only 31.4% (SD 37.7). Strategies to reduce UPF consumption in New Zealand adolescents could include encouraging family meals, reduced or healthier snacking, and increased eligibility and uptake of the government-funded school lunch programme.