Yes / Young people choose energy-dense, nutrient-poor diets, yet understanding of potential determinants is limited. Associations between food choices, mental wellbeing, health-related quality of life (HRQoL) and family affluence were explored to identify targets for intervention to promote dietary health and wellbeing in young people. Adolescents were recruited via post-primary schools in the UK and surveyed at two time-points when aged 13-14 years and 15-16 years. The questionnaire enquired about mental wellbeing using the Short Warwick-Edinburgh Mental Wellbeing Scale, HRQoL using the KIDSCREEN-10, socio-economic status using the Family Affluence Scale and food choice by Food Frequency Questionnaire (FFQ). With missing and anomalous cases excluded, the sample comprised 1208 cases. Factor analysis on the FFQ indicated five food choice factors: ‘Junk Food’; ‘Meat’; ‘Healthy Protein’; ‘Fruit/Vegetables’; ‘Bread/Dairy’. Multivariate regression analysis indicated that frequent consumption of Junk Food was associated with being male and lower mental wellbeing. Frequent Meat intake was associated with being male and with lower HRQoL. Frequent choice of Bread/Dairy foods was more common among males and associated with higher wellbeing and greater affluence. Those who consumed Fruit/Vegetables frequently were more likely to be female, have higher HRQoL, higher mental wellbeing, and greater family affluence. These direct associations endured between time points. The dietary factors were not mutually exclusive. Those who frequently chose Junk Food were less likely to choose Fruit/Vegetables. Frequent choice of Meat was associated with more frequent choice of Junk Food and Healthy Protein. Intervention to improve dietary and psychological health in young people should target males, those in less affluent households, seek to reduce consumption of ‘junk’ food, and increase fruit and vegetable intake. / This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. This ma-terial is based upon work conducted as part of the Wellbeing in Schools (WiSe) study which was financially supported by the Centre of Excel-lence for Public Health (Northern Ireland), and the Centre of Evidence and Social Innovation, at Queens University Belfast.

Yes / Wellbeing declines during adolescence, for which the reasons are unclear. This analysis explored associations between wellbeing and multiple lifestyle, socioeconomic and school-level factors in young people. Data were collected as part of the Wellbeing in School (WiSe) survey of adolescent school children in Northern Ireland at age 13-14 years (N=1618; 49% female) and 15-16 years (N=1558; 50.5% female). Wellbeing was assessed using the short-form Warwick-Edinburgh Mental Wellbeing Scale (sWEMWBS), where scores declined between time one (13-14 years) and time two (15-16 years) in both sexes and were significantly lower in females at both timepoints. Multilevel, multivariate modelling was therefore undertaken separately for males and females with sWEMWBS scores as the dependent variable. Physical activity, family affluence, fruit and vegetable intake, social media use, sleep duration, school factors (size and type) and religion were independent variables. More frequent physical activity in both sexes at both timepoints was associated with higher sWEMWBS scores. In females, higher sWEMWBS scores were associated with less social media use at time one (and marginally at time two), greater family affluence at time two, and being Catholic at both timepoints. In males, higher sWEMWBS scores were associated with more frequent fruit and vegetable intake at time one. Mental wellbeing was unrelated to sleep duration or school factors in either sex, at both time points. Efforts to maximize mental wellbeing in adolescents should promote engagement in physical activity and implement sex-specific interventions. / This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. This material is based upon work conducted as part of the Wellbeing in Schools (WiSe) study which was financially supported by the Centre of Excellence for Public Health (Northern Ireland), and the Centre of Evidence and Social Innovation, at Queens University Belfast.