Investigate the efficacy of a dissonance-based (DB) intervention (i.e., the Body Project), during which some examples of intuitive eating were provided by peer leaders, in improving intuitive eating and targeting risk and protective factors for eating disorders (ED) among Brazilian women with body dissatisfaction. Participants were randomized to a four-session DB intervention (n = 38) or assessment-only control (AOC) (n = 36), and completed validated measures assessing intuitive eating, body appreciation, self-esteem, body-ideal internalization, body dissatisfaction, negative affect, and disordered eating pre-intervention, post-intervention, and at 4- and 24-week follow-ups. The DB condition demonstrated significantly greater increases in intuitive eating, body appreciation and self-esteem scores compared to AOC from pre-intervention to post-intervention (between-condition Cohen's d = 0.73-0.98), 4-week (between-condition Cohen's d = 1.25-1.87) and 24-week follow-up (between-condition Cohen's d = 0.82-1.38). Also, the DB condition showed significantly greater decreases in body-ideal internalization, body dissatisfaction and disordered eating scores from pre-intervention to post-intervention (between-condition Cohen's d = 0.76-1.04), 4-week (between-condition Cohen's d = 1.27-1.71) and 24-week follow-up (between-condition Cohen's d = 1.04-1.19). Regarding negative affect, DB condition showed significantly greater reduction only at 24-week follow-up (between-condition Cohen's d = 0.60). Results reinforce the efficacy of DB interventions in reducing ED risk factors for young women and support the preliminary efficacy of these programs in improving intuitive eating, body appreciation, and self-esteem. Level I, randomized controlled trial. ReBEC (Brazilian Registry of Clinical Trials; available at http://www.ensaiosclinicos.gov.br/ ) number of registration: RBR-2f57cs. Date of registration: June 1, 2020.