Background: The aim of the research is to explore the relationship between psychological factors and nutritional status in adolescence. The issue of adolescent nutrition is related to several psychological problems, as well as to developmental changes during this period. Research on body image dissatisfaction has confirmed that most adolescents are dissatisfied with their bodies. Developmentally oriented scientists are unique in their approach to explaining the problem of body image, focusing on multiple aspects and attempting to understand the intrapersonal and interpersonal factors that are important for the formation of body image. Methods: The sample included 260 adolescents aged 11 to 15. The assessment of sociodemographic factors, emotional states, physical activity levels, and eating habits was included in the questionnaires filled out by the parents (DASS-21 and the Physical Activity & Nutrition Behaviors Monitoring Form questionnaire). Body Mass Index (BMI) was calculated based on information about the height and weight of the adolescents. Results: The results of the correlation between psychological characteristics and BMI indicate a negative low correlation with all psychological aspects: depression (r = −0.25; p < 0.05), anxiety (r = −0.30; p < 0.05), and stress (r = −0.28; p < 0.05). Over 70% of adolescents are classified in the category of normal BMI. Conclusions: The results indicate that subjects who are of normal weight experience less pronounced depression, anxiety, and stress.