Sodium benzoate (E211)

What is Sodium benzoate?

Sodium benzoate is the sodium salt of benzoic acid, a compound that occurs naturally in cranberries, prunes, plums, cinnamon and cloves. The commercial version is manufactured, and it is used because it dissolves easily in water while benzoic acid itself does not.

On labels it appears as sodium benzoate, sometimes benzoate of soda, and in Europe as E 211. You will often see it alongside potassium sorbate (E 202), which covers a slightly different range of microbes.

Why is Sodium benzoate used in food?

Sodium benzoate only works in acidic conditions — below roughly pH 4.5 — because that is where it converts back into benzoic acid, the form that actually penetrates microbial cells. That is why you find it almost exclusively in sour products: carbonated soft drinks, fruit juices and juice drinks, salad dressings, pickles, condiments, jams and some sauces.

It is cheap, tasteless at use levels and effective against molds and yeasts, which are the main spoilage risk in acidic foods. Without a preservative of this kind, most shelf-stable dressings and drinks would need refrigeration, pasteurization, or a much shorter shelf life.

Is Sodium benzoate safe? What the research says

What regulators say. In the US, sodium benzoate is affirmed as Generally Recognized as Safe (GRAS) under 21 CFR 184.1733, with FDA noting that current usage results in a maximum of 0.1% of the food. EFSA re-evaluated benzoic acid and the benzoates in 2016 and set an acceptable daily intake (ADI) of 5 mg per kg of body weight per day, expressed as benzoic acid. The WHO/FAO expert committee (JECFA) revisited the same data in 2021 and raised its group ADI to 0–20 mg/kg, after concluding that the previous adjustment for differences between people was more conservative than the evidence required. The two bodies disagreeing by a factor of four is a good reminder that an ADI is a safety margin, not a threshold of harm.

Intake in children. EFSA's 2016 exposure assessment is the reason this additive gets a moderate rating here rather than a low one. Under a "brand-loyal" scenario — a toddler or child who drinks the same flavored beverage regularly — estimated intake exceeded the ADI. Once benzoates carried over from other ingredients were counted, intake could rise two- to threefold for high-level consumers, pushing some children over the ADI even without brand loyalty. The main contributors were flavored drinks and, perhaps surprisingly, unprocessed fruits and vegetables, where benzoic acid occurs naturally.

Benzene in drinks. This is the concern people usually mean when they ask about sodium benzoate. In beverages that contain both a benzoate and ascorbic acid (vitamin C), benzene — a known human carcinogen — can form at parts-per-billion levels, and heat and light speed it up. FDA tested roughly 200 beverages between 2005 and 2007: most had no detectable benzene or levels well below the benchmark, ten exceeded it, and after manufacturers reformulated, retested products came in below 1.5 ppb. FDA's conclusion was that the levels found do not pose a safety concern; for comparison, the EPA limit for benzene in drinking water is 5 ppb. The practical fix — which industry adopted — is to avoid combining benzoate with added vitamin C, or to add a chelating agent.

Hyperactivity in children. Sodium benzoate was one of the seven additives in the 2007 Southampton study (McCann et al., The Lancet), which found that mixtures of synthetic colors plus sodium benzoate increased hyperactive behavior in some 3- and 8–9-year-old children. Because only mixtures were tested, the study cannot say whether sodium benzoate contributed at all, and EFSA concluded the findings were not a basis for changing its ADI. The EU warning label that came out of that study applies to six colors — not to sodium benzoate.

Allergic-type reactions. A small number of people, more often those with chronic hives (urticaria) or asthma, report reactions to benzoates. This is uncommon, and it is an intolerance rather than a true allergy.

Bottom line: at the levels used in food this is a well-characterized preservative, and the benzene issue has been managed by reformulation. The one practical takeaway is for households where a young child drinks a lot of the same flavored beverage every day.

Sodium benzoate regulation: US vs EU

Sodium benzoate is permitted in the US, the EU, the UK and Canada and is not the subject of any current ban, phase-out or state restriction. It does not appear on FDA's list of chemicals under post-market review. EFSA's 2016 opinion recommended that the European Commission consider the exposure findings for children; JECFA's 2021 revision of the group ADI means the two main authorities now use different figures. Check the latest status: rules can change.

Who should limit or avoid Sodium benzoate?

• Young children who drink a lot of one flavored beverage. This is the group EFSA singled out. Varying drinks, or diluting them, addresses it without needing to avoid the additive entirely.
• People with chronic hives or aspirin-sensitive asthma. Benzoate intolerance is uncommon but is reported more often in these groups. Worth discussing with a doctor rather than self-diagnosing.
• Anyone drinking a lot of soda with added vitamin C. The benzene risk is small and largely resolved, but storing such drinks cool and out of sunlight is sensible anyway.
• Anyone reducing ultra-processed foods. Sodium benzoate is a marker of shelf-stable processed drinks and condiments; cutting those usually improves the diet more than avoiding this one ingredient does.