How is the meat categorized by the International Agency for Research on Cancer?
The International Agency for Research on Cancer (IARC) categorized processed meats (PMs) as a ‘Group 1 Carcinogen’ for colorectal cancer (CRC). CRC is the third most frequently diagnosed cancer globally. Studies have observed an increase in CRC incidence parallel to the adoption of a western diet. One aspect of the western diet that has been scrutinized is the carcinogenicity of PMs. As a well-respected global authority, the IARC is largely considered a reputable source. This categorization fuelled a negative perception of the IARC and PMs and is a central issue driving the meat and cancer controversy.
PMs refers to meat that has been modified through salting, smoking or curing and most contain red meats. Chan et al. highlights consuming PM significantly contribute to CRC. This study focused on the formation of carcinogenic chemicals from processing including polycyclic aromatic hydrocarbons (PAH). However, Genkinger et al. report that PMs are not the primary reason for CRC but rather, meat intake is correlated with higher energy intake thus leading to obesity, increasing the risk of carcinogen formation. Another suggested hypothesis is the high cooking temperatures of meat. Magalhaes et al. in his systematic review report PAH’s generated from meat cooked over an open flame cause DNA damage. However, Lam et al. argue little direct evidence exists that this occurs following consumption of meat.