**8. Risk and protective factors for colorectal polyps and colorectal cancer summary**

Our data show that colorectal polyps and cancer share common risk and protective factors (Kotzev et al., 2008). This finding, paired with the high frequency of existence of colorectal polyps and CRC, could serve as an evidence of the role of the colorectal polyps as CRC precursors. Common risk and protective factors for colorectal polyps and colorectal cancer are summarized in Table. 6, where factors are divided into alimentary risk factors, nonalimentary risk factors and protective factors.
