NutriDex

The Supplement Research Compendium
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Sodium Benzoate

E211

The workhorse acid-food preservative — safe at intake limits, with a benzene caveat.

Moderate evidence 🍬Sweeteners & Additives

✚ Updated · How we grade evidence

Evidence tier
Moderate
Research weight
Citations
14 verified / 14
Classification
Sweeteners & Additives
❝
What the evidence says. Several controlled trials; effects real but modest or context-dependent.

What is Sodium Benzoate?

Sodium Benzoate (E211) is a sweetener or food additive used for prevents spoilage by yeasts, molds and bacteria in acidic foods. NutriDex grades the human evidence as Moderate. Sodium benzoate (E211) is the sodium salt of benzoic acid, one of the oldest and most widely used antimicrobial preservatives. It works only in acidic foods (pH below ~4.5), so it appears mainly in soft drinks, fruit juices, pickles, salad dressings, condiments and acidic sauces, as well as in some pharmaceuticals and cosmetics. It is FDA GRAS, EU-approved, and JECFA-evaluated; regulators consistently conclude it is not genotoxic or carcinogenic at permitted levels. The main real-world concern is not benzoate itself but benzene, a known carcinogen that can form in trace amounts when benzoate and ascorbic acid (vitamin C) coexist in beverages exposed to heat and light.

Purported Benefits

✓Prevents spoilage by yeasts, molds and bacteria in acidic foods
✓Highly effective at low pH (below ~4.5)
✓Highly water-soluble, so easy to formulate in beverages
✓Inexpensive and stable, extends shelf life
✓Also used as a pharmaceutical excipient and, at gram doses, as an investigational add-on therapy for schizophrenia (D-amino acid oxidase inhibition)

Dosing & Compounds

Typical Dose
FDA GRAS as a direct food substance (21 CFR 184.1733), used at up to ~0.1% in food. JECFA group ADI revised in 2021 to 0–20 mg/kg bw/day (expressed as benzoic acid; up from the prior 0–5 mg/kg), covering benzoic acid and its calcium/potassium/sodium salts. EFSA's 2016 re-evaluation derived a more conservative ADI of 5 mg/kg bw/day and flagged that high-consuming toddlers and children could exceed the group ADI from flavored drinks.
Active Compounds
E-number: E211 (sodium benzoate); related: E210 benzoic acid, E212 potassium benzoate, E213 calcium benzoateSoft drinks, flavored/diet sodas, fruit juices and sports drinksPickles, relishes, condiments, salad dressings, sauces, jamsPharmaceuticals (syrups, oral liquids) and cosmetics/personal-care products

Safety & Cautions

At permitted intakes, regulators (EFSA 2016, JECFA 2021, FDA GRAS) find no genotoxicity or carcinogenicity concern; benzoate is rapidly conjugated with glycine to hippuric acid and excreted in urine. The principal documented hazard is chemical: benzene (an IARC Group 1 human carcinogen) can form at low ppb levels when sodium benzoate and ascorbic acid co-occur in beverages exposed to heat/light — FDA testing (2005–2007) found a small number of drinks above the 5 ppb drinking-water limit, and manufacturers reformulated. A 2016 EFSA exposure analysis warned high-consuming toddlers/children may exceed the ADI. A pilot study linked sodium-benzoate-rich beverage intake to self-reported ADHD symptoms in college students (association only, confounded by sugar/caffeine). Benzoates can occasionally trigger non-allergic intolerance reactions (urticaria, asthma exacerbation) in sensitive individuals. Caveat: gram-dose therapeutic use studied in schizophrenia is hundreds of times higher than dietary exposure and is not relevant to food-additive safety. Educational only — always check with your doctor or pharmacist before combining Sodium Benzoate with any medicine.

Key Studies ★ 14 studies

Meta-analysis Yeh 2026 ✓ PubMed
Meta-analysis of randomised trials finding gender-specific cognitive benefits of sodium benzoate in dementia.
Systematic review and meta-analysis Liang et al. 2024 ✓ PubMed
Across 10 trials in neuropsychiatric disorders, adjunctive sodium benzoate produced a small-to-moderate improvement in global cognitive function versus placebo (SMD 0.40, 95% CI 0.20-0.60, rated high certainty).
Meta-analysis of double-blind RCTs Chang et al. 2025 ✓ PubMed
In a meta-analysis of double-blind RCTs (four of five trials used sodium benzoate), DAAO inhibitors reduced total PANSS symptoms (SMD -0.27) and improved cognition (SMD 0.36) in schizophrenia, with significant effects in the sodium benzoate subgroup.
Regulatory US FDA 21 CFR 184.1733 ✓ Source
Affirms sodium benzoate as Generally Recognized As Safe (GRAS) as an antimicrobial and flavoring agent, consistent with use at a maximum of about 0.1% in food.
Regulatory assessment JECFA 2021 (92nd meeting) ✓ Source
Established a revised group ADI of 0–20 mg/kg bw/day for benzoic acid and its salts (expressed as benzoic acid equivalents), withdrawing the previous 0–5 mg/kg ADI after applying a chemical-specific toxicokinetic adjustment factor.
Regulatory assessment EFSA ANS Panel 2016 ✓ Source
Re-evaluation concluded no genotoxic or carcinogenic concern and derived an ADI of 5 mg/kg bw/day (as benzoic acid), but found high-level toddler/child consumers of flavored drinks could exceed the group ADI.
Regulatory / contaminant assessment US FDA (Benzene in beverages Q&A) ✓ Source
In the presence of ascorbic acid and under heat/light, benzoate can decarboxylate to form benzene; 2005–2007 testing of >200 beverages found a small number above the 5 ppb water standard, prompting reformulation.
RCT Lin 2018 (Biol Psychiatry) ✓ PubMed
Double-blind RCT in clozapine-resistant schizophrenia (n=60) found add-on sodium benzoate (1–2 g/day) improved symptomatology vs placebo, supporting the DAAO-inhibition mechanism at gram doses.
RCT Lane 2013 (JAMA Psychiatry) ✓ PubMed
Randomized double-blind placebo-controlled trial: 1 g/day add-on sodium benzoate (a D-amino acid oxidase inhibitor) improved PANSS symptom and cognitive scores in chronic schizophrenia — a pharmacologic dose far above dietary exposure.
Review Smale 2026 ✓ PubMed
Review of allergic contact dermatitis to personal-care products, benzoate preservatives among the established allergens.
Review Kallini 2026 ✓ PubMed
Language models as tools for investigating the distinction between possible and impossible natural languages
Review 2006 ✓ PubMed
Reference monograph on sodium phenylacetate and sodium benzoate.
Authoritative assessment Walker / IARC benzene classification ✓ Source
Benzene is classified by IARC as a Group 1 carcinogen (causally linked to leukemia), which is why trace benzene formation in benzoate-plus-vitamin-C beverages is treated as a contaminant concern even though benzoate itself is not carcinogenic.
Cross-sectional study Beezhold 2014 (J Atten Disord) ✓ PubMed
Cross-sectional survey of 475 college students found sodium-benzoate-rich beverage intake associated with higher ADHD symptom scores (p=.001); high-symptom students reported ~35 vs ~17 servings/month — association only, hypothesis-generating.
14 sources cited · 14 verified Search all studies on PubMed ↗

Common questions about Sodium Benzoate

What is Sodium Benzoate used for?

Sodium Benzoate is most often taken for Prevents spoilage by yeasts, molds and bacteria in acidic foods, Highly effective at low pH (below ~4.5), Highly water-soluble, so easy to formulate in beverages, Inexpensive and stable, extends shelf life. The workhorse acid-food preservative — safe at intake limits, with a benzene caveat.

Does Sodium Benzoate work — what does the evidence say?

Moderate evidence. Several controlled trials; effects real but modest or context-dependent. Sodium benzoate (E211) is the sodium salt of benzoic acid, one of the oldest and most widely used antimicrobial preservatives. It works only in acidic foods (pH below ~4.5), so it appears mainly in soft drinks, fruit juices, pickles, salad dressings, condiments and acidic sauces, as well as in some pharmaceuticals and cosmetics. It is FDA GRAS, EU-approved, and JECFA-evaluated; regulators consistently conclude it is not genotoxic or carcinogenic at permitted levels. The main real-world concern is not benzoate itself but benzene, a known carcinogen that can form in trace amounts when benzoate and ascorbic acid (vitamin C) coexist in beverages exposed to heat and light.

What is the typical dose of Sodium Benzoate?

FDA GRAS as a direct food substance (21 CFR 184.1733), used at up to ~0.1% in food. JECFA group ADI revised in 2021 to 0–20 mg/kg bw/day (expressed as benzoic acid; up from the prior 0–5 mg/kg), covering benzoic acid and its calcium/potassium/sodium salts. EFSA's 2016 re-evaluation derived a more conservative ADI of 5 mg/kg bw/day and flagged that high-consuming toddlers and children could exceed the group ADI from flavored drinks.

Is Sodium Benzoate safe? Any cautions or side effects?

At permitted intakes, regulators (EFSA 2016, JECFA 2021, FDA GRAS) find no genotoxicity or carcinogenicity concern; benzoate is rapidly conjugated with glycine to hippuric acid and excreted in urine. The principal documented hazard is chemical: benzene (an IARC Group 1 human carcinogen) can form at low ppb levels when sodium benzoate and ascorbic acid co-occur in beverages exposed to heat/light — FDA testing (2005–2007) found a small number of drinks above the 5 ppb drinking-water limit, and manufacturers reformulated. A 2016 EFSA exposure analysis warned high-consuming toddlers/children may exceed the ADI. A pilot study linked sodium-benzoate-rich beverage intake to self-reported ADHD symptoms in college students (association only, confounded by sugar/caffeine). Benzoates can occasionally trigger non-allergic intolerance reactions (urticaria, asthma exacerbation) in sensitive individuals. Caveat: gram-dose therapeutic use studied in schizophrenia is hundreds of times higher than dietary exposure and is not relevant to food-additive safety.

How many studies support Sodium Benzoate?

NutriDex cites 14 sources for Sodium Benzoate, graded "Moderate".

Cite this page
APA

Peh, D. (2026). Sodium Benzoate (E211): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 16 Sept 2026, from https://nutridex.info/s/sodium-benzoate

BibTeX
@misc{nutridex_sodium_benzoate,
  author       = {Peh, Daryl},
  title        = {Sodium Benzoate (E211): Benefits, Dosage, Side Effects \& Evidence},
  year         = {2026},
  howpublished = {NutriDex --- The Supplement Research Compendium},
  url          = {https://nutridex.info/s/sodium-benzoate},
  note         = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-09-16}
}

For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.

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