E252 — Potassium nitrate
E252 (Potassium nitrate), a preservative, is rated "avoid": worth avoiding. Saltpetre. Used in traditional dry-cured meats and some cheeses. Converts to nitrite in the body, then potentially to colorectal-cancer-linked nitrosamines.
What is Potassium nitrate?
Saltpetre, used since medieval times to cure meats and prevent spoilage in some hard cheeses. Found in traditional hams, salami, and some Dutch and Swiss cheeses.
What does it do to the body?
Your gut and saliva convert it to nitrite, which can then react with proteins in meat to form nitrosamines tied to colon cancer. Daily processed-meat eaters are at highest risk.
What regulators say
IARC classifies processed meats containing nitrates as Group 1 (known carcinogen). EU regulations cap the permitted maximum level in cured meat and cheese.
Risk rating: Avoid
Known or suspected to cause harm: a substance EFSA or another regulator has flagged, or one restricted in some jurisdictions. Best kept out of a regular diet.
Source: WHO Q&A — processed meat (Group 1) ↗