Examining the influence of socio-economic factors on ultra-processed food consumption patterns of UK adolescents.

Objective: Ultra-processed food (UPF) consumption varies with socio-economic status (SES) in adults, and evidence suggests that similar patterns exist in adolescents. However, the relationship remains understudied in this critical developmental group. This study aimed to further characterise adolescent UPF consumption and its relationship with SES by exploring dietary patterns within UPF consumption.

Design: Using food-diary data, adolescents' UPF intake was quantified and categorised. Principal component and clustering analysis were used to identify dietary patterns. Associations of these dietary patterns with socio-demographic characteristics were then analysed.

Setting: Pooled data from the rolling, cross-sectional National Diet and Nutrition Survey, waves 1-to-11 (2008-2019).

Subjects: UK adolescents (11- to18-year-olds) (n 3199).

Results: Three UPF dietary patterns were identified: (i) the 'Restrictive' pattern, which included the lowest total consumption of UPF (95 % CI: 33·1, 34·9 % g/d), but elevated consumption of UPF often perceived as healthy, was associated with adolescents of a higher SES; (ii) the 'Permissive' pattern included 61·6 % g/d (95 % CI: 60·3, 63·0 % g/d) total UPF, dominated by 'ready-to-eat,' low nutrient-density UPF, and was associated with adolescents of a lower SES and (iii) the 'Traditional' pattern had moderate consumption of total UPF (95 % CI: 47·6, 50·9 % g/d) with higher intake of UPF used in home-cooking and had less distinct associations with SES.

Conclusion: Results suggest that SES impacts both the amount and type of UPF consumed by adolescents in the UK, underscoring the importance of this factor when designing interventions. Distinct dietary patterns within adolescents' high UPF diets have potential behavioural, nutritional and health implications.