Longitudinal associations between stress, packaged snack consumption, chronic fatigue and emotional symptoms in...

Adolescence is marked by heightened stress and health-related behavioral changes. This study examined whether chronic fatigue mediates longitudinal associations of stress and packaged snack consumption with emotional symptoms in adolescents. Participants were drawn from the Queensland Twin Adolescent Brain cohort (baseline N = 373, follow-up N = 279; mean interval 1.7 years). Measures included the Daily Life Stressors Scale (DLSS), Australian Child and Adolescent Eating Survey-packaged snacks (AES-packsnack), Somatic and Psychological Health Report-fatigue (SPHERE-f), and Strengths and Difficulties Questionnaire-emotional symptoms (SDQ-emo). Structural equation modeling with full information maximum likelihood was used. Pubertal status was assessed via the Sexual Maturation Scale, with exploratory subgroup analyses by sex and puberty stage. Baseline DLSS (β = 0.157, p < 0.001) and AES-packsnack (β = 0.192, p = 0.002) significantly predicted follow-up SPHERE-f, which in turn predicted follow-up SDQ-emo (β = 0.078, p = 0.006). SPHERE-f mediated both associations. Baseline DLSS and AES-packsnack were significantly correlated (β = 0.37, p < 0.05). Model fit was acceptable (CFI = 0.952, TLI = 0.840, RMSEA = 0.053). The fatigue-emotion pathway was more pronounced in females (β = 0.101, p = 0.011) than males (β = 0.043, p = 0.280), and the stress - snack correlation was significant only in females (β = 0.492, p = 0.023). Mid-puberty showed the strongest stress - fatigue (β = 0.180, p < 0.001) and snack - fatigue (β = 0.260, p = 0.020) associations. Chronic fatigue is a key pathway linking stress and packaged snack consumption to adolescent emotional symptoms. Interventions targeting stress management and healthier dietary behaviors, accounting for sex- and puberty-specific differences, may reduce fatigue-related emotional difficulties.