Food preservatives, rated
Preservatives stop food going off, which is genuinely useful. But they are also one of the more concerning additive groups: 17 of the 24 here are worth avoiding, and they fall into three families most people would recognise. Here is the full picture, with the reason for each.
The three groups doing most of the work on the avoid list are nitrites and nitrates (the curing agents in bacon, ham and salami), sulfites (in dried fruit, wine and some sauces), and benzoates (in fizzy drinks). Each has a specific, documented concern rather than a vague one. The rest, including a few natural-acid preservatives, are far less of an issue.
Avoid · 17
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.
E203 — Calcium sorbate
A mould and yeast inhibitor. EFSA withdrew its approval in the EU in 2018 after genotoxicity concerns it…
AvoidE210 — Benzoic acidA preservative in soft drinks, pickles, and sauces. In acidic drinks it can react with vitamin C to form…
AvoidE211 — Sodium benzoateThe sodium salt of benzoic acid. The standard preservative in soft drinks, sauces, and pickles. Can form…
AvoidE212 — Potassium benzoateThe potassium salt of benzoic acid. Same benzene-formation concern as sodium benzoate when combined with…
AvoidE220 — Sulphur dioxideA pungent preservative in wine, dried fruit, and processed shellfish. Triggers asthma attacks in about 1% of…
AvoidE221 — Sodium sulphiteA sulphite preservative used in wine, dried fruit, and processed potato. Same asthma-trigger concern as…
AvoidE222 — Sodium bisulphiteA sulphite preservative used in wine and fruit products. Same asthma-trigger concern as the rest of the…
AvoidE223 — Sodium metabisulphiteThe most common form of sulphite preservative in dried fruit, wine, and pickled foods. Asthma trigger in…
AvoidE224 — Potassium metabisulphiteThe potassium version of metabisulphite. Standard wine and brewing preservative. Same asthma-trigger concern…
AvoidE225 — Potassium sulphiteA sulfite preservative. Sulfites trigger asthma attacks in sensitive people and must be declared as an…
AvoidE226 — Calcium sulphiteA sulphite preservative used in some wines and brewing. Same asthma-trigger concern for the roughly 1% of…
AvoidE227 — Calcium bisulphiteA sulphite preservative used in brewing and some fruit products. Same asthma-trigger concern as the rest of…
AvoidE228 — Potassium bisulphiteA sulphite preservative used in winemaking and some processed foods. Same asthma-trigger concern as the rest…
AvoidE249 — Potassium nitriteA preservative used in cured meats. During cooking it can form nitrosamines, compounds linked to colorectal…
AvoidE250 — Sodium nitriteThe standard curing salt for bacon, ham, and hot dogs. Can form nitrosamines during cooking, linked to…
AvoidE251 — Sodium nitrateA preservative in cured meats that converts to nitrite in the body, then potentially to nitrosamines linked…
AvoidE252 — Potassium nitrateSaltpetre. Used in traditional dry-cured meats and some cheeses. Converts to nitrite in the body, then…
AvoidWatch · 4
Mixed evidence or a specific concern (gut, allergy, or contested safety data). Not alarming, but worth keeping an eye on rather than eating without limit.
E200 — Sorbic acid
A widely used preservative that stops mould and yeast in cheese, bread, and dried fruit. Generally safe but…
WatchE202 — Potassium sorbateThe potassium salt of sorbic acid. The most widely used preservative in cheese, yogurt, dried fruit, and…
WatchE242 — Dimethyl dicarbonateA cold-sterilant sprayed into soft drinks, iced teas and wine. It breaks down almost entirely into methanol…
WatchE282 — Calcium propionateThe calcium salt of propionic acid. Standard mould preventer in supermarket bread. A small 2002 trial linked…
WatchSafe · 3
Cleared by EFSA with no significant concern at typical dietary exposure. Common, well-studied, and not a reason to put a product back on the shelf.
E262 — Sodium acetates
The salt of vinegar. Used as a preservative and to give salt-and-vinegar crisps their tang. EFSA found no…
SafeE280 — Propionic acidA natural fatty acid used to prevent mould in bread and processed cheese. Your gut bacteria produce it from…
SafeE1105 — LysozymeAn egg-white enzyme used as a preservative in cheese and wine. Allergen risk for people sensitive to egg, who…
SafeFrequently asked questions
Which food preservatives should you avoid?
Of the 24 preservatives we track, 17 are rated avoid. They cluster into three families: nitrites and nitrates (used in cured meats), sulfites (in dried fruit, wine and some processed foods), and benzoates (in soft drinks). Those three account for most of the concern.
Why are nitrites and nitrates a concern?
In cured and processed meats, nitrites (E249, E250) and nitrates (E251, E252) can form nitrosamines, compounds linked to bowel cancer. This is the main reason processed meat carries a health warning. The preservative role is real, but so is the trade-off.
Are sulfites bad for you?
Sulfites (E220 to E228) are a recognised allergen and can trigger asthma-like reactions in sensitive people, which is why they must be declared on labels. For most people in small amounts they are tolerated, but they are one to watch if you react to them.
Are all preservatives bad?
No. A few, such as those derived from natural acids, rate as safe, and preservation itself prevents genuinely dangerous spoilage and food poisoning. The point is not to fear preservatives as a category, but to know which specific ones carry a real concern.