Adolescents with diet-dependent chronic illness: motivation for healthy eating and well-being

Type 1 diabetes (T1D) and life-threatening food allergies (FAs) are two diet-dependent chronic illnesses (DDCIs) that require rigorous self-management centered on strict dietary monitoring. Grounded in self-determination theory, this study aimed to investigate differences in motivation for healthy eating and well-being among adolescents coping with DDCI, compared to individuals without DDCI. Additionally, it explored the mediating role of general health practices in the relationship between motivation for healthy eating and well-being. A total of N = 116 adolescents, aged 10-18 years (T1D: N = 36, M±SD age = 15.28 ± 1.85; FA: N = 39, M±SD age = 13.31 ± 2.40; no-DDCI: N = 41, M±SD = 14.71 ± 1.76), completed questionnaires assessing motivation for healthy eating, general health practices, and well-being. Internal motivation for healthy eating was positively associated with general health practices in all 3 groups. A moderated-mediation model revealed that among adolescents with DDCI, internal motivation for healthy eating was positively associated with psychological well-being. Internal motivation was also positively associated with physical well-being, but only among adolescents with FA. Conversely, only among adolescents with T1D, external motivation for healthy eating was negatively associated with psychological and physical well-being. Lack of motivation for healthy eating was negatively associated with general health practices among adolescents with T1D and individuals without DDCI. Adolescents with DDCI face challenges in adhering to healthy eating recommendations and translating knowledge into action. Targeted interventions are necessary to enhance internal and autonomously driven motivation for dietary changes. Personalized nutrition programs for adolescents living with DDCI may effectively promote self-management and overall well-being in this population.