A critical overview on the biological and molecular features of red and processed meat in colorectal carcinogenesis

J Gastroenterol. 2017 Apr;52(4):407-418. doi: 10.1007/s00535-016-1294-x. Epub 2016 Dec 2.


A recent investigation by the World Health Organisation (WHO) has found that the consumption of processed meat and potentially red meat promotes carcinogenesis and can increase the risk of colorectal cancer. This literature review aims to summarise both the red and processed meat molecules associated with colorectal carcinogenesis and investigate their relationship with the pathogenic process of colorectal cancer. Literature relating to the carcinogenic effect of red and processed meat molecules was critically reviewed. There are multiple molecules present in red and processed meat with a potential carcinogenic effect on colorectal tissues. Processed meat is more carcinogenic compared to red meat because of the abundance of potent nitrosyl-heme molecules that form N-nitroso compounds. Studies have also noted that other molecules such as polycyclic aromatic hydrocarbons and heterocyclic amines have potential mechanisms for the initiation of colorectal cancer pathogenesis. The non-human sugar molecule N-glycolylneuraminic acid may account for the carcinogenic effects of pork despite its heme content being comparable to that of chicken. Red meat products, especially those that have been processed, have a wide variety of carcinogenic molecules known to increase the risk of colorectal cancer. Thus, the outcome of this review is consistent with the recent findings of WHO.

Keywords: Carcinogenesis; Colorectal; Meat; Molecules; Processed meat; WHO.

Publication types

  • Review

MeSH terms

  • Carcinogenesis*
  • Carcinogens / analysis
  • Carcinogens / toxicity
  • Colorectal Neoplasms / etiology*
  • Food Handling*
  • Heme / adverse effects
  • Humans
  • Meat / adverse effects*
  • Meat / analysis
  • Meat Products / adverse effects
  • Meat Products / analysis
  • Nitroso Compounds / adverse effects
  • Red Meat / adverse effects
  • Red Meat / analysis


  • Carcinogens
  • Nitroso Compounds
  • Heme