Frequently Asked Question
Health & NutritionCancer: processed meat and colorectal cancer
Last reviewed: January 9, 2026
Summary
The IARC classified processed meat as carcinogenic to humans (Group 1) based on sufficient evidence in humans, with the strongest link to colorectal cancer. Red meat was classified as “probably carcinogenic” (Group 2A).
Supported by 5 cited sources
Evidence Summary
- Mechanisms include N-nitroso compounds and other process/cooking-related carcinogens.
- Risk is dose-related; small amounts daily raise risk relative to lower intake. Evidence quality: High (consensus evaluation) Limitations / nuance: “Group 1” indicates confidence in causation, not that risk magnitude equals tobacco; magnitude depends on dose. Bottom line: Processed meat causally increases colorectal cancer risk; reducing it is evidence-aligned.
Supporting Evidence
Sources:
- World Health Organization (WHO). WHO guidelines on use of medically important antimicrobials in food-producing animals (2017)
- Zhang Y, et al.. Nitrite/nitrate in meat processing and nitrosation. (2023)
- WHO/FAO/OIE One Health resources .
- World Health Organization / International Agency for Research on Cancer. Carcinogenicity of consumption of red meat and processed meat (2015)
- IARC Press Release. URL: https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf (2015)
Sources:
- World Health Organization (WHO). WHO guidelines on use of medically important antimicrobials in food-producing animals (2017)
- Zhang Y, et al.. Nitrite/nitrate in meat processing and nitrosation. (2023)
- WHO/FAO/OIE One Health resources .
- World Health Organization / International Agency for Research on Cancer. Carcinogenicity of consumption of red meat and processed meat (2015)
- IARC Press Release. URL: https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf (2015)
Sources:
- World Health Organization (WHO). WHO guidelines on use of medically important antimicrobials in food-producing animals (2017)
- Zhang Y, et al.. Nitrite/nitrate in meat processing and nitrosation. (2023)
- World Health Organization / International Agency for Research on Cancer. Carcinogenicity of consumption of red meat and processed meat (2015)
- IARC Press Release. URL: https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf (2015)
- WHO/FAO/OIE One Health resources .
Sources & Evidence
5 sources cited across 3 claims
1
Processed meat is classified as carcinogenic (IARC Group 1)
Systematic ReviewWHO guidelines on use of medically important antimicrobials in food-producing animals — World Health Organization (WHO) (2017)View source ↗
Carcinogenicity of consumption of red meat and processed meat — World Health Organization / International Agency for Research on Cancer (2015)View source ↗
URL: https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf — IARC Press Release (2015)View source ↗
2
Red meat is probably carcinogenic (IARC Group 2A)
Systematic ReviewWHO guidelines on use of medically important antimicrobials in food-producing animals — World Health Organization (WHO) (2017)View source ↗
Carcinogenicity of consumption of red meat and processed meat — World Health Organization / International Agency for Research on Cancer (2015)View source ↗
URL: https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf — IARC Press Release (2015)View source ↗
3
N-nitroso compounds link processed meat to cancer
MechanisticWHO guidelines on use of medically important antimicrobials in food-producing animals — World Health Organization (WHO) (2017)View source ↗
Carcinogenicity of consumption of red meat and processed meat — World Health Organization / International Agency for Research on Cancer (2015)View source ↗
URL: https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf — IARC Press Release (2015)View source ↗