Diet and Food chemicals increasing the risk of colorectal cancer – literature review

Colorectal cancer is a common form of cancer nowadays. There are many risk factors in the pathogenesis of colorectal cancer. The malignant proliferation is caused by one or more genetic mutations, which activate oncogenes and deactivate tumor suppressor genes. Some factors cannot be changed, such as a person's age or family history. An essential aspect in the pathogenesis of colorectal cancer is the choice of lifestyles, such as a high-fat diet, smoking, and excess alcohol. Carcinogens can be either natural or chemical. The mechanisms by which carcinogens initiate tumor formation are genetic or non-genotoxic. The most common form of colorectal cancer is found in people who ingest chemicals that, once ingested, reach the large intestine, thus causing malignant lesions. The Western diet and the metabolic syndrome are risk factors for colorectal cancer, due to gut microbiota changes and low-grade chronic inflammation. Among the most important diet carcinogens are nitrosamines, hydrazines, organophosphates, acetaldehyde, and heterocyclic amines. Screening programs, especially among people over 50 years of age, and with multiple risk factors are extremely important in detecting colorectal cancers in the early stages and in improving the long-term prognosis in such patients.