PurposeThe aim of this study was to explore head and neck cancer (HNC) patient experiences of a novel dietitian delivered health behaviour intervention.MethodsThis study is a qualitative study which employed semi-structured individual interviews using open and axial coding and then final selective coding to organise the data. Patients with HNC who had participated in a dietitian delivered health behaviour intervention to reduce malnutrition were invited to discuss their experience of this intervention. Individual interviews were conducted, transcribed and analysed using grounded theory.ResultsNine patients participated in the interviews. Four dimensions were identified in the initial coding process: ‘information’, which described patients’ desire for tailored advice during their treatment; ‘challenges of treatment experience’, which described the difficulties related to treatment side effects; ‘key messages: importance of eating and maintaining weight’, which covered perceived integral messages delivered to patients by dietitians; and ‘dietitian’s approach’ describing patient experiences of empathic and compassionate dietitians. Two overarching themes resulted from examining the connections and relationships between these dimensions: ‘survival’, a connection between eating and living; and ‘support’, describing the valued working partnership between dietitian and patient.ConclusionsDimensions and themes overlapped with the qualitative literature on HNC patient experience of treatment. However, some themes, such as the empowerment of a message linking eating to survival, appeared unique to this study. Patients found this message to be delivered in a supportive manner that motivated change.Electronic supplementary materialThe online version of this article (10.1007/s00520-017-4029-5) contains supplementary material, which is available to authorized users.