Exploring the relationship between Premenstrual Dysphoric Disorder (PMDD) and disordered eating: a qualitative study Background: Premenstrual dysphoric disorder (PMDD) causes debilitating psychological and physical symptoms during the luteal phase of the menstrual cycle. Previous research has shown a strong association between PMDD and disordered eating; however, there is limited research from the UK on the impact that PMDD has on eating behaviours. This information is needed to inform appropriate interventions and support. This study aimed to explore the eating behaviours of people living with PMDD in the UK, their experiences of seeking support, and considerations for future interventions. Method: Qualitative semi structured interviews were conducted with 13 people with PMDD living in the UK. The participants were recruited via an online PMDD support page. The interviews were audio-recorded, transcribed verbatim and thematically analysed. Results: Six themes emerged: ‘dual personality’ life with PMDD; the struggle for appropriate PMDD management; the destructive impact of life with PMDD; eating behaviours during a PMDD episode; ‘aftermath’ (the impact of disordered eating); and accessing support for PMDD-related eating behaviours. Participants described PMDD as severe and distressing, impacting every aspect of their lives. Obtaining an accurate diagnosis and management were challenging, involving dismissive encounters with health professionals, misdiagnoses, and inappropriate treatment. Their eating behaviours fluctuated during different menstrual phases, showing disordered patterns consistent with binge eating disorder, bulimia nervosa, and anorexia nervosa. Many ‘managed’ their eating habits with harmful strategies such as purging and ‘fad diets’. Participants reported both psychological and physical health impacts of their eating behaviour. Few participants sought eating support, and those who did found minimal improvement. Barriers to seeking help included previous ‘dismissive’ attitudes and a lack of PMDD knowledge among health professionals. Participants recommended PMDD-specific training for health professionals, specialised eating disorder services, increased information dissemination, and flexible management options. Conclusion: People with PMDD display disordered eating consistent with eating disorders such as binge eating disorder, bulimia nervosa, and anorexia nervosa. This highlights the need for a greater understanding of the potential shared mechanisms of eating disorders and PMDD. Given that the majority of people with eating disorders are women and individuals assigned female at birth, understanding the relationship with PMDD is integral to shaping appropriate interventions and eating support strategies. See more of our research at www.pmddresearch.com