section_path: Health effects/Cancer
section_name: Cancer
paragraph_text: Cancer
  
  The consumption of processed and red meat carries an increased risk of cancer. The International Agency for Research on Cancer (IARC), a specialized agency of the World Health Organization (WHO), classified processed meat (e.g., bacon, ham, hot dogs, sausages) as, "carcinogenic to humans (Group 1), based on sufficient evidence in humans that the consumption of processed meat causes colorectal cancer." IARC classified red meat as "probably carcinogenic to humans (Group 2A), based on limited evidence that the consumption of red meat causes cancer in humans and strong mechanistic evidence supporting a carcinogenic effect."
  
  Cancer Research UK, National Health Service (NHS) and the National Cancer Institute have stated that red and processed meat intake increases risk of bowel cancer. The American Cancer Society in their "Diet and Physical Activity Guideline", stated "evidence that red and processed meats increase cancer risk has existed for decades, and many health organizations recommend limiting or avoiding these foods." The Canadian Cancer Society have stated that "eating red and processed meat increases cancer risk".
  
  A 2021 review found an increase of 11–51% risk of multiple cancer per 100g/d increment of red meat, and an increase of 8–72% risk of multiple cancer per 50g/d increment of processed meat.
  
  Cooking muscle meat creates heterocyclic amines (HCAs), which are thought to increase cancer risk in humans. Researchers at the National Cancer Institute published results of a study which found that human subjects who ate beef rare or medium-rare had less than one third the risk of stomach cancer than those who ate beef medium-well or well-done. While eating muscle meat raw may be the only way to avoid HCAs fully, the National Cancer Institute states that cooking meat below 100 °C (212 °F) creates "negligible amounts" of HCAs. Microwaving meat before cooking may reduce HCAs by 90%. Nitrosamines, present in processed and cooked foods, are carcinogenic, being linked to colon cancer. Polycyclic aromatic hydrocarbons, present in processed, smoked and cooked foods, are similarly carcinogenic.