Nitrites and nitrates: why is E250 in processed meat debated?

On the label of salami, sausages and ham you may have seen "preservative: sodium nitrite (E250)" or "sodium nitrate (E251)." These substances keep cured meat pink and contribute to microbiological safety. They also come up whenever the link between processed meat and cancer is discussed. Reading what two institutions say separately helps put the debate in the right place.

Which code is which?

• E249 potassium nitrite, E250 sodium nitrite
• E251 sodium nitrate, E252 potassium nitrate

Nitrates can be converted to nitrite in the body and in some products, so the two groups are usually assessed together.

What EFSA says

The European Food Safety Authority (EFSA) re-evaluated both groups in 2017:

• Nitrites (E249, E250): the opinion set an acceptable daily intake (ADI) of 0.07 mg nitrite ion per kg body weight per day, very close to earlier values (SCF 1997: 0-0.06; JECFA 2002: 0-0.07). Intake from additive use stayed within the ADI for the general population, with a slight exceedance in children at the highest percentile.
• Nitrates (E251, E252): in its opinion the existing ADI (3.7 mg/kg/day) was not changed. Nitrate used as an additive makes up less than 5% of total dietary nitrate. When all sources, including natural presence and contamination, are counted, the ADI is exceeded in all age groups.
• Nitrosamines: for nitrosamines that nitrite can form in the body the margin of exposure is above 10,000; for nitrosamines already present in meat products, the margin at high exposure is below 10,000. According to trade press coverage, EFSA judged nitrite's contribution to overall nitrosamine exposure to be of "low concern for health" when used at approved levels.
• Epidemiology: the panel noted links between dietary nitrite and gastric cancer, and between nitrite and nitrate from processed meat and colorectal cancer. Animal carcinogenicity results were negative.

What IARC says

In 2015 the International Agency for Research on Cancer (IARC) classified processed meat in Group 1 ("carcinogenic to humans") and red meat in Group 2A ("probably carcinogenic"). Each 50 grams of processed meat eaten daily raises the risk of colorectal cancer by 18%. Two things should be kept apart:

• The classification reflects the strength of the evidence, not the size of the risk. Individual risk is small and rises with the amount eaten.
• It applies to processed meat itself, not to a single additive. As EFSA also notes, nitrite's share in that link cannot be fully separated out.

Reading the label

1. Look for E249-E252 under "preservative"; they appear on salami, sausages, ham and cured meats.
2. Even on "nitrite-free" or "no additives" products, nitrate can come from plant-based extracts, so the ingredients list remains the reference.
3. Total consumption matters: the debate concerns frequent, large intakes of processed meat.
4. Natural nitrate comes mainly from vegetables and water; this article is about the amounts added as additives.

In LogicFood's research records

In LogicFood's records E250 and E251 carry the highest risk level (High). The marker is a prioritisation signal based on institutional statements about processed meat and cancer; it is not a verdict that a product is dangerous in itself.

In short

EFSA says the safe limits for nitrite and nitrate used as additives at approved levels do not need to change; IARC places processed meat itself in the carcinogen category. They answer different questions. Recognising these substances on a label helps you decide, knowingly, how often to eat such products.

Sources: EFSA, re-evaluation of nitrites (E 249, E 250), 2017 · EFSA, re-evaluation of nitrates (E 251, E 252), 2017 · FoodNavigator, EFSA on nitrites and nitrates, 2017 · IARC press release, processed and red meat, 2015