Preservatives
Nitrates and nitrites
Definition
What it is
Nitrate/nitrite preservative: forms carcinogenic nitrosamines when heated. IARC classified processed meats containing nitrites as Group 1 carcinogens.
On the label
Label names covered by this flag
- nitrates and nitrites
- sodium nitrite
- sodium nitrate
- potassium nitrite
- potassium nitrate
Regulation
Regulatory status
- Canada Restricted
- European Union Restricted
Explainer
In plain language
Nitrates and nitrites are curing salts used to preserve meat, keep its pink or red color, and add the characteristic tang of cured products. Sodium and potassium nitrate and nitrite are the common forms, and nitrate can convert to nitrite during curing. They also help prevent the growth of the bacteria that cause botulism, which is one reason they are used in processed meats.
Assessment
Why it is flagged
The main concern is nitrosamines, compounds that can form when nitrites react with proteins, especially under high heat like frying. In 2015 the International Agency for Research on Cancer classified processed meat as a Group 1 carcinogen, meaning there is sufficient evidence that eating processed meat is associated with colorectal cancer at a population level. That classification is about processed meat as a whole, and nitrites are one of the mechanisms studied. It does not mean any single serving is dangerous, and the size of individual risk depends on how much and how often someone eats these foods. Nitrates and nitrites are still permitted with limits, and vegetables also contain nitrates in a different dietary context. Clear Label flags them so processed-meat exposure is visible and testable over time.
In the aisle
Where it commonly shows up
- Bacon and breakfast sausage
- Hot dogs and frankfurters
- Deli meats and cold cuts
- Cured ham and salami
- Pepperoni and other cured pizza toppings
- Jerky and cured snack meats
- Some smoked fish
Practical
Reading the label
Look for sodium nitrite, sodium nitrate, potassium nitrite, or potassium nitrate. Products labeled 'uncured' or 'no nitrates added' often still use celery powder or celery juice, which is a natural nitrate source that behaves similarly, so those claims do not always mean nitrite-free.
Alternatives
If you want to avoid it
Some people choose fresh meats over cured ones, or reserve processed meats for occasional use. Where a recipe allows, cooking cured meats at lower temperatures produces fewer nitrosamines than high-heat frying.
FAQ
Common questions
Does 'uncured' bacon really have no nitrites?
Usually not. Uncured products are typically cured with celery powder or juice, which is a natural source of nitrate that converts to nitrite. The chemistry ends up similar even though the label reads differently.
What did IARC actually classify?
In 2015 IARC classified processed meat as a Group 1 carcinogen based on evidence linking it to colorectal cancer at a population level. The classification reflects strength of evidence, not the size of risk from any one meal.
Aren't nitrates in vegetables too?
Yes, vegetables like leafy greens and beets contain nitrates. The dietary context differs, since vegetables also supply compounds like vitamin C that reduce nitrosamine formation, which is one reason researchers treat the two sources differently.
Citations
Sources
Citation
Primary reference
About this page: the definition, label names, severity, and regulatory chips come from the clearlabel ingredient taxonomy, the same data the scanner uses to score products. Research summaries describe associations reported in published studies, not diagnoses; individual responses vary. Scan any product with clearlabel to see which of its ingredients carry flags.