The World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) has routinely published dietary and lifestyle recommendations aimed at reducing the risk of colorectal cancer (CRC) and improving overall patient outcomes.1,2,3 In 2018, the most recent report (Third Expert Report) was released and included recommendations such as high vegetable and fruit intake, at least 30 grams of fiber daily, limited alcohol intake, maintaining a healthy weight, and avoiding intake of processed foods high in fat and sugars.2
Until recently, the actual impact of how patient adherence to these recommendations impacted CRC risk had not been fully elucidated. Therefore, a recent study conducted by Petimarand colleagues sought to investigate the link between patient compliance to the recommended diet and malignancy risk by developing a lifestyle score based on the 2018 recommendation across 2 separate cohorts: the Nurses’ Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS) from 1986 to 2012.1
The NHS contains approximately 131,701 female nurses within the US aged 30 to 55 years, while the HPFS included 51,529 male health professionals aged 40 to 75 years in the US. Within these cohorts, those patients with ulcerative colitis, a history of cancer (except for nonmelanoma skin cancer), who were missing baseline data (weight, physical activity, information on the food frequency questionnaire (FFQ), and excessive (>3500-4200 kcal/day) or minimal caloric intake (<500-800 kcal/day) were excluded.
Based on the data found in these cohorts and the 2018 WCRF/AICR recommendations, the study authors developed a lifestyle score that aimed to measure the patients’ adherence to a dietary regimen. The main dietary recommendations from the 2018 report were centered on 7 components/items: fruits and vegetables, dietary fiber, whole grains and legumes, refined grains and processed foods, red and processed meats, sugar-sweetened beverages, and alcohol. Adherence was measured using a score of 0 (nonadherence), 0.5 (partial adherence), or 1 (adherence). The definitions of adherence were developed from the WCRF/AICR criteria. The average of these 7 dietary items was then calculated and labeled as the “diet score.” The overall WCRF/AICR lifestyle score was then derived using this diet score along with adiposity and physical activity data.