Drivers of Dietary Choice After a Diagnosis of Colorectal Cancer: A Qualitative Study

Dietary changes often accompany management of a cancer diagnosis, but how and why patients with colorectal cancer (CRC) make dietary decisions requires further investigation. To learn about patients’ food-related beliefs and understand whether and why dietary changes were made by patients starting chemotherapy after a CRC diagnosis. A qualitative semi-structured interview study was conducted as a secondary analysis among a subset of patients with stages II-IV CRC enrolled at baseline in a randomized controlled trial. Twenty-nine patients participated in the interview. Data were collected at the University of Alberta (Edmonton, Alberta, Canada) from 2016–2019 before any trial intervention. Audio-recorded interviews were transcribed verbatim then coded inductively by two research team members. Qualitative content analysis was applied to capture emergent themes. Patients reported varied degrees of dietary change that stemmed from internal and external influences. Four main themes emerged to describe patients’ dietary decisions after a CRC diagnosis: 1) Medical Influences: eating to live; 2) Health Beliefs: connecting lived experiences with new realities; 3) Static Diets: no changes postdiagnosis; and 4) Navigating External Influences: confluence of personal agency and social constraints. The extent to which patients altered their dietary choices depended on perspectives and beliefs. These included the degree to which dietary decisions provided some agency (ie, feeling of control) for dealing with physical ramifications of cancer treatment, individuals' personal understandings of healthy foods, and the role of diet in managing their new physical reality postdiagnosis. This information provides registered dietitian nutritionists and health care providers with insight into dietary intentions of select patients being treated for CRC. These findings can guide future research focused on effective strategies for streamlined nutritional support that aligns with patient needs.