Disordered eating, unhealthy weight-control behaviours and body dissatisfaction are associated with diminished mental health. A key aspect that has been identified for the development of disordered eating behaviours and body dissatisfaction is to be teased. Additionally, the literature suggests that weight may affect the relationship between weight-teasing and disordered eating and body dissatisfaction, although this pattern is unclear. This study presents two cross-sectional studies with an adult and an adolescent sample. The adolescent sample comprised 15,224 participants, and the adult sample comprised 321 participants, all from Spain. Hierarchical regression analyses were conducted. Aims: to assess the relations among disordered eating, body dissatisfaction, weight, and weight-teasing among adolescents and adults; and to examine whether weight-teasing, weight, age, and gender predict disordered eating and body dissatisfaction in adults and adolescents. The results showed that adolescent girls presented greater effects, and all interactions were significant between weight-teasing and eating disorders. Adults also showed greater effects for women, and only eating disorder interactions were significant. Weight-control behaviours did not show any relationship with weight-teasing. Conclusion: Different approaches may be used in the prevention of eating disorders. Our results show that weight-teasing affects adults differently from adolescents.