Cancer Risk from Processed Meats and Red Meats
The International Agency for Research on Cancer (IARC), the specialized cancer agency of the World Health Organization (WHO), recently released a report declaring red meat and processed meats to be carcinogenic to humans. The review does not ask people to stop eating these meats but indicates that by reducing consumption of these products, they can reduce their risk of getting colorectal cancer. Because of this report, there has been a lot of interest in the World Health Organization’s classification of meats as carcinogens.
Classifications listed in the report include Group 1 carcinogens and Group 2A carcinogens. Group 1 carcinogens indicate that there is convincing evidence from epidemiological studies that the item causes cancer. This now includes processed meats causing colorectal cancer. Other concerns like tobacco smoking and asbestos are also in this group, however the lifetime risks are different. Red meat is listed as 2A indicating that it is probably carcinogenic based on limited evidence and strong mechanistic evidence. Analysis of data from 10 studies estimated that for every 50 grams (about 2 bacon slices) eaten daily the risk of colorectal cancer is increased by about 18%. (The American Cancer Society estimates a lifetime risk of colorectal cancer being 4.49% for females and 4.84% for males so extrapolating this would mean for every 50 grams of processed meat consumed over a lifetime the risk would increase to 5.29% for females and 5.71% for males). Colorectal cancer screening is highly effective at preventing the disease and according to the American Cancer Society’s Colorectal Cancer Facts and Figures 2014-2016, men and women age 50 and older at average risk should be screened and earlier if there is a family history.
It is important however to keep this context in terms of risk reduction. Lung cancer remains the most preventable form of cancer death in the world (Cancer Facts & Figures, 2014). According to the World Health Organization, tobacco use causes 20% of global cancer deaths and around 70% of lung cancer deaths. If you do not smoke and you are not exposed to second hand smoke, other modifiable risk factors to keep in mind include maintaining a healthy weight, being physically active and eating healthy. It is recommended to have a nutritious diet that includes eating from the cruciferous family, like broccoli and kale; and from the allium family, which has garlic and onions. Other items to eat on a regular basis are fruit, beans, nuts and seeds.
For clarification of the specific meat categories mentioned in the IARC report:
- Red meat is mammalian muscle meat including beef, veal, pork, lamb, mutton, horse and goat.
- Processed meat refers to meat that has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavor or improve preservation. Most processed meats contain pork or beef but processed meats may also contain other red meats, poultry, offal, or meat by-products, such as blood. Examples of processed meat include hot dogs (frankfurters), ham, sausages, corned beef, and biltong or beef jerky as well as canned meat and meat-based preparations and sauces.
For IARC’s press release on their report, go to: http://www.iarc.fr/en/media-centre/pr/2015/pdfs/pr240_E.pdf
For IARC’s news report publication in the Lancet http://www.thelancet.com/pdfs/journals/lanonc/PIIS1470-2045(15)00444-1.pdf
To read World Health Organization’s response to requests for clarification on the publication of the report, go to: http://www.who.int/mediacentre/news/statements/2015/processed-meat-cancer/en/
Colorectal Cancer Facts and Figures, 2014-2016: http://www.cancer.org/acs/groups/content/documents/document/acspc-042280.pdf
For assistance in nutrition planning, contact the Simms/Mann Center to make an appointment with Integrative Oncology Specialist Carolyn Katzin, MS, CNS, MNT. For more information, go to https://www.simmsmanncenter.ucla.edu/?p=344 or call 310 794-6644. Inquiries welcomed.