The intention of this paper is to explore how societal food choices may be affecting our clients’ mentation and to discuss alternative drivers behind their feelings of anger, sadness and fear that potentially lead to fixed moods of anxiety and depression. The current perception of nutrition within psychotherapy is framed within lifestyle, self-care enquiry and a rich, metaphorical use of digestive systems within the therapeutic process. Yet over the last two decades the synthesis of nutritional therapy with psychiatry has theorized a network of ideas under the umbrella title of ‘nutritional psychiatry ’, which links positivist research to suggest poor diet and gut microbiome health are also factors behind the development of mental illnesses. The differing epistemological positions in these two fields create a challenge to the case study used which explores working psychotherapeutically with a client's food choices, whilst interrogating whether nutritional psychiatric-derived theories relate to the client work and how to incorporate these ideas within psychotherapeutic practice.