Processed meat is meat that’s been preserved or changed; by smoking, curing, salting, canning or adding preservatives. These types of meats includes ham, bacon, salami and sausages, and processed white meats like chicken nuggets and sliced lunch meats. Red meat includes all fresh, minced, and frozen beef, pork and lamb.
Fresh white meats, like chicken and fish, have not yet been linked to any increased risk of cancer – although increased presence of carcinogens and toxins in fresh-water fish, due to contaminant exposure, are anther issue. Cantonese-style salted fish has also been linked to increasing risks of cancer.
Cancers processed and red meat are linked to
Research has found that consuming lots of red meat can increase the risk of bowel cancer, meaning there is lots of good evidence of a link, but we need a more quality studies to be certain. In contrast it has been shown that processed meat is a direct cause of cancer – the link is as certain as other proven causes of cancer, like tobacco.
There is also increasing evidence that eating processed and red meats increases the risk of stomach and pancreatic cancer, but more research is needed.
Eating less processed and red meat
Cut down consumption by making small changes like :
- Meat-free Mondays – pick a day to cut out meat entirely
- Find new recipes with fresh chicken or fish instead of processed or red meat
- Substituting meat in your usual meals for pulses, like beans or lentils
- Try a pledge – go vegetarian or even vegan for a month and explore the fantastic array of meat-free options available these days
- Reduce portions – have one sausage instead of two, and replace this with more hearty vegetables
Switching to more expensive or organic processed and red meat won’t does not affect one’s cancer risk. The way to lower one’s cancer risk is to reduce all types of processed and red meats.
How much processed and red meat can one eat?
Research has pointed to an increased risk of cancer for every 25g of processed meat one eats a day – roughly equal to a rasher of bacon or a slice of ham. If you’re consuming processed and red meat most days, now’s the time to start cutting down.
Basically the less one eats the lower the risk, so cutting down is good for the health no matter how much meat is eaten.
How does processed and red meat cause cancer?
Chemicals added during processing, or produced when cooking, can increase the risk of cancer.
These chemicals include :
This is naturally found in red meat and processed red meat. It can damage cells, and cause bacteria in the body to produce harmful chemicals. This can increase the risk of cancer.
Used as a preservative to keep processed meat fresher for longer, nitrites can become cancer-causing chemicals like N-nitroso compounds or NOCs. These chemicals are linked to reasons why processed meat increases the risk of cancer more than fresh red meat. Processed meats aren’t the only foods that contain these chemicals of course. In fact, many vegetables also contain high amounts – mainly nitrates – a good reason to eat organic.
- Heterocyclic amines (HCAs) and polycyclic amines (PCAs)
Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) are chemicals formed when muscle meat, including beef, pork, fish, or poultry, is cooked using high-temperature methods, such as pan frying or grilling directly over an open flame. They can damage cells in the bowel, and studies have shown the chemicals to be associated with increased risks of colorectal, pancreatic, and prostate cancer.
Brown KF, Rumgay H, Dunlop C, et al. The fraction of cancer attributable to modifiable risk factors in England, Wales, Scotland, Northern Ireland, and the United Kingdom in 2015. British Journal of Cancer. 2018;118:1130-1141.
International Agency for Research on Cancer. Red Meat and Processed Meat. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. 2018. Vol 114. https://publications.iarc.fr/Book-And-Report-Series/Iarc-Monographs-On-The-Identification-Of-Carcinogenic-Hazards-To-Humans/Red-Meat-And-Processed-Meat-2018.
NHS. Red meat and the risk of bowel cancer. 2019. https://www.nhs.uk/live-well/eat-well/red-meat-and-the-risk-of-bowel-cancer/#portion-sizes-and-cutting-down2018.
World Cancer Research Fund. Diet, Nutrition, Physical Activity and Cancer: a Global Perspective. A summary of the Third Expert Report 2018. https://www.wcrf.org/dietandcancer.
The Conversation – Why nitrates and nitrites in processed meats are harmful – but those in vegetables aren’t. https://theconversation.com/why-nitrates-and-nitrites-in-processed-meats-are-harmful-but-those-in-vegetables-arent-170974.