Diet and Lifestyle Habits in Early-Onset Colorectal Cancer: A Pilot Case-Control Study

Background: Early-onset colorectal cancer (eoCRC), defined as a colorectal cancer (CRC) in patients younger than 50 years old, shows an increasing incidence worldwide in the latest years. The role of exogenous factors associated with CRC has been largely overlooked in eoCRC. Here, we conducted a case-control study to evaluate the diet and the lifestyle habits in an Italian population of patients with eoCRC, compared to age-matched healthy controls (HCs). Methods: We enrolled 118 subjects (47 cases, 71 controls) in a third-level academic hospital. We analyzed epidemiological features (age, sex, body mass index), lifestyle behaviors (smoking habits, physical activity, type of diet, use of dietary supplements), and eating habits (semiquantitative food-frequency questionnaire) in eoCRCs and HCs, covering the previous 5 years. Results: In our cohort, positive family history of CRC was significantly associated with the development of eoCRC (p = 0.004). Fresh meat (p = 0.003), processed meat (p < 0.001), dairy products (p = 0.013), and smoking (p = 0.0001) were significantly associated with eoCRC compared to controls. Other variables did not differ significantly between the two groups. Conclusion: Fresh and processed meat, dairy products, and smoking could be considered significant risk factors for eoCRC, although further confirmation by international multicenter studies is desirable. Diet and smoking could be the main areas of future interventions for eoCRC primary prevention.