Social media platforms may be promising intervention tools to address the nutrition literacy and associated health behaviours of young women. We aimed to co-design a lifestyle intervention on social media targeting eating, physical activity, and social wellbeing that is evidence-based, acceptable, and engaging for young women aged 18-24 years. The study used a participatory design framework and previously published iterative mixed methods approach to intervention development. Matrices for workshop objectives were constructed using expert discussions and insights were sought from young women in participatory workshops. A 10-step qualitative data analysis process resulted in relevant themes, which guided intervention development. The resulting intervention, the Daily Health Coach, uses multiple features of Instagram to disseminate health information. Co-created nutrition content considers themes such as holism, food relationships, and food neutrality and acknowledges commonly experienced barriers associated with social media use such as nutrition confusion, body image concerns, and harmful comparison. This study may guide other researchers or health professionals seeking to engage young women in the co-design of women's health promotion or intervention content on social media.
Keywords: behaviour change; digital health; nutrition; social media; young women.