Diet is increasingly recognised as an important target for dementia prevention, with healthier dietary patterns associated with slower cognitive decline and lower dementia risk.(1,2) Nutrition may influence dementia through multiple pathways, including vascular and metabolic health, inflammation and oxidative stress.(3) However, the relevance and uptake of dietary guidance may depend on its cultural and practical applicability. As part of the co-design of MindCare Digital, a culturally responsive digital dementia prevention program, this study examined how food and nutrition guidance could be culturally adapted for South Asian, Middle Eastern, Sub-Saharan African and Pacific Islander communities. A community-based participatory co-design approach was used. A three-day cultural adaptation workshop involving 29 scientific, community and consumer stakeholders informed development of the draft intervention, which was subsequently reviewed in nine community workshops with 157 participants across Australia: South Asian (n = 36), Middle Eastern (n = 37), Sub-Saharan African (n = 41), Pacific Islander (n = 40), and three community service providers. Participants were predominantly women (60.5%), and most were aged 45-64 years. Using the World Café approach, participants reviewed intervention content, cultural relevance and delivery. For this analysis, data relating specifically to food, diet and nutrition were extracted and thematically analysed to identify cross-community and community-specific priorities for cultural adaptation. The cultural adaptation workshop showed that nutrition guidance needed to build on existing dietary practices rather than require substantial departure from culturally familiar ways of eating. Stakeholders emphasised retaining traditional foods while making achievable changes to portion size, cooking methods and ingredient use, and identified affordability, food availability and migration-related changes in eating habits as important constraints on dietary change. These findings were reinforced in the community workshops. Across communities, participants sought clearer portion guidance and practical ways to make familiar meals healthier rather than replacing staple foods with unfamiliar alternatives drawn predominantly from Western or Mediterranean dietary patterns. Community-specific priorities differed in emphasis: South Asian participants highlighted vegetarian options and guidance on traditional oils; Middle Eastern participants emphasised accommodating fasting practices; Sub-Saharan African participants prioritised affordability and familiar staple foods; and Pacific Islander participants emphasised culturally familiar root vegetables and the communal context of eating. Participants also sought realistic, affordable substitutions and practical modifications to traditional dishes. For the digital resource, they preferred concise, plain-language information supported by culturally recognisable food imagery and cooking demonstrations showing how dietary changes could be incorporated into everyday eating practices. Collectively, these findings highlight the importance of culturally responsive nutrition education that supports feasible dietary change without displacing culturally meaningful foods. These insights informed refinement of MindCare Digital. The final modules will undergo user testing before evaluation in a national randomised controlled trial and will be made freely available to multicultural communities, with potential for broader adaptation.