Adherence to a paleolithic diet and paleolithic-like lifestyle is associated with lower colorectal cancer risk.

PURPOSE: Evidence regarding the associations between the paleolithic diet (PD) score, the paleolithic-like lifestyle (PLL) score, and colorectal cancer (CRC) risk remains limited. This study aimed to investigate these associations in a Chinese population. METHODS: We analyzed data from 2792 CRC cases and 2785 matched controls in a large-scale case–control study. The PD score was constructed based on 14 dietary components, while the PLL score integrated the PD score with physical activity, body mass index, and smoking. Multivariable unconditional logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Nonlinear dose-response relationships were assessed using restricted cubic spline (RCS) regression. RESULTS: Participants in the highest quartile of PD adherence had a significantly lower CRC risk compared to those in the lowest quartile (OR 0.73; 95% CI 0.62–0.86). A stronger inverse association was observed for the highest quartile of PLL adherence (OR 0.56; 95% CI 0.47–0.66). These inverse associations were consistently observed across CRC subtypes (colon and rectal cancers). RCS analyses revealed linear inverse dose-response relationships (all Pnonlinear > 0.05). CONCLUSIONS: Our findings suggest that adherence to a paleolithic dietary pattern and its associated lifestyle may offer protective benefits against CRC in Chinese.