ObjectiveTo analyze the dietary risk factors and protective factors for the occurrence of colorectal cancer, and to provide the basis for the prevention of colorectal cancer.

MethodsA case-control study was conducted with 55 newly diagnosed colorectal cancer patients from Minhang Hospital Affiliated to Fudan University from January to March 2021 as the case group.Simultaneously, 96 non-colorectal cancer patients matched for age, gender, and region during the same period were selected as the control group.A food frequency questionnaire was utilized for face-to-face surveys of the subjects, with single factor analysis conducted using non-parametric tests and χ² tests, and multi-factor analysis via conditional logistic regression.

ResultsSingle factor analysis results indicated a correlation between colorectal cancer and factors such as animal offal, dark vegetables, fungi, fresh milk, yogurt, beef, poultry, nuts, pickled foods, eggs, educational level, and occupation.Logistic regression analysis results revealed that animal offal (OR=3.471, 95%CI: 1.395-8.634) increased the risk of colorectal cancer, while dark vegetables (OR=0.131, 95%CI: 0.036-0.482), fungi (OR=0.245, 95%CI: 0.083-0.726), fresh milk (OR=0.243, 95%CI: 0.085-0.696), and eggs (OR=0.221, 95%CI: 0.086-0.570) decreased the risk.

ConclusionsAnimal offal is a risk factor for colorectal cancer, while dark vegetables, fungi, poultry, and eggs serve as protective factors.