Diet, environmental factors and increasing incidence of colorectal cancer in Nigeria

Colorectal cancer (CRC) in Nigeria used to be a rare disease. However, over the last 40 years it has gradually become a significant health concern. Several publications on this disease from Nigeria have documented an increase in the incidence. To suggest possible and credible pathogenesis for the observed increase in CRC incidence in Nigeria, a search through AJOL, PubMed, and Google Scholar using search items like "colon cancer in Nigeria," "rectal cancer in Nigeria," and "CRC in Nigeria" was carried out. Also, a search for known risk factors in the development of CRC such as diet, carcinogens in red meat, alcohol, and polyposis coli syndromes were also initiated. Factors responsible for the increase in CRC incidence in Nigeria include poor refrigeration facilities resulting from poor electricity services; leading to deep-fried, smoked and charcoal-grilled meat. Other risk factors include an affinity for consumption of offal, an increase in obesity, proliferation of fast food joints, and an increase in alcohol intake. It is unclear how long and large the factors that cause CRC in a patient will have to be present before developing the disease. A dietary intake of fresh, wholesome, non-processed, preservative and hydrocarbon free foods should be encouraged; while habits such as consumption of alcohol and cigarette smoking are discouraged.