Objective: Anaemia is a health problem for adolescents in India. This paper examines the nuanced transformations triggered by a multi-pronged, community-based anaemia intervention with adolescents and their families, seeking meaningful insights for future nutrition and anaemia programmes. Design: Qualitative study rooted in critical theory. Setting: Three slum communities -- Dharavi and Kandivali (in Mumbai) and Kalwa (in Thane) in Maharashtra, India. Methods: Data were collected through focus-group discussions and in-depth interviews with young people, parents and other stakeholders. Content analysis of drawings of a nutritious food plate by participants supplemented discussion and interview data. Thematic analysis was undertaken manually using a grounded theory approach. Findings: Nutrition education with adolescents and parents led to reduced junk food consumption although reinforcement of the information provided was necessary to sustain the change. Parental support was a crucial factor in ensuring anaemia treatment compliance but was affected by a lack of awareness regarding the consequences of anaemia and the nutritional requirements of anaemic adolescents. Other factors, including the pampering of boys, the neglect of girls and the heavy workload of mothers influenced treatment compliance. Awareness and agency among adolescents contributed to a supportive environment in terms of raised consciousness and better sanitation within families and the community. Conclusion: Findings highlight the need for a holistic approach to address anaemia among young people. While nutrition and health education are important to address treatment noncompliance, this approach should also focus on factors such as socioeconomic status, gender equity, health prioritisation, family involvement and engaging young people as agents of change to promote an enabling environment.