Safety grading ORANGE – SOME CONCERNS
Sodium benzoate (E211) is a widely used preservative in acidic foods and beverages. It is considered generally safe at approved levels by both the European Food Safety Authority (EFSA) and the U.S. Food and Drug Administration (FDA). However, it carries some health concerns. When combined with ascorbic acid (Vitamin C), sodium benzoate can form benzene, a known carcinogen, especially under heat and light exposure. Additionally, some studies have linked sodium benzoate consumption to hyperactivity in children and potential allergic reactions such as asthma, skin rashes, or hives.
Because of these risks, sodium benzoate is classified here as ORANGE — SOME CONCERNS. While legal and common in food products, it is best consumed in moderation and avoided where possible, especially in products with high Vitamin C content.
Should You Avoid Sodium Benzoate?
If you are sensitive to preservatives, have asthma, or are concerned about children’s behavior, it may be wise to limit sodium benzoate intake. While not banned, its safety profile raises caution, particularly when consumed frequently through soft drinks, processed juices, or sauces. Occasional consumption is not expected to pose major health risks, but continuous high intake should be avoided.
Common Uses
- Carbonated soft drinks and fruit juices (to prevent microbial growth)
- Pickles, sauces, and salad dressings (to extend shelf life)
- Jams, jellies, and fruit preserves (to inhibit spoilage)
- Pharmaceutical syrups and medicines (as preservative)
- Cosmetics and personal care products (anti-fungal agent)
Common names / Synonyms
- Benzoate of soda
- Sodium salt of benzoic acid
- INS 211
What is it?
Sodium benzoate is the sodium salt of benzoic acid, a simple aromatic carboxylic acid. In its natural form, benzoic acid is found in small amounts in berries such as cranberries, plums, and apples. Industrially, sodium benzoate is produced by neutralizing benzoic acid with sodium hydroxide. The result is a crystalline powder that is highly soluble in water and effective in acidic conditions (pH below 4.5).
Its preservative function is due to the ability of benzoic acid (once released in acidic foods) to penetrate microbial cell walls and disrupt enzymatic activity, thereby preventing the growth of bacteria, yeasts, and molds. Sodium benzoate is particularly effective in carbonated beverages, which are naturally acidic. It is less effective in neutral or alkaline foods.
Although generally recognized as safe at low concentrations (up to 0.1% in food), concerns arise from its chemical reactivity with ascorbic acid. Under certain storage conditions, benzene – a compound linked to cancer may form in small quantities. Regulators monitor this closely, and manufacturers are encouraged to avoid formulations combining sodium benzoate and Vitamin C.
Where it’s allowed (EU vs US)
In the European Union, sodium benzoate is permitted as a food additive under strict maximum levels.
In the United States, the FDA recognizes sodium benzoate as GRAS (Generally Recognized as Safe) with similar restrictions on usage levels.
Further reading
- EU Food and Feed Information Portal Database
- Wikipedia – Sodium Benzoate
- PubMed Search – Sodium Benzoate
Peter W. Piper: Potential Safety Issues Surrounding the Use of Benzoate Preservatives
5. Conclusions
Even if we do not consume foods and drinks that contain benzoate or sorbate, we may still be exposed to small amounts of these compounds through our diet. These organic acids occur naturally at a high level in many berries. Benzoate can arise from the hippuric acid occurring naturally at concentrations of up to 50 mg/kg in milk and milk products [32,33,34]. It also forms during cheese ripening [35]. The benzoate originating from dietary hippuric acid is generated mainly through the actions of our gut microbes [4]. Benzoic acid is also one of the metabolites of cinnamon, the oral feeding of cinnamon powder having been found to generate benzoate in the blood and brain of mice [29,36].
The central issue is whether a much higher dietary intake of benzoate has the potential to exert detrimental effects (many beverages contain levels of sodium benzoate just under the regulatory level of 150 mg/L [34]). In mice, short-term consumption of sodium benzoate impairs memory performance [37]. In addition there are indications that a high intake of sodium benzoate may be linked to attention deficit–hyperactivity disorder in children [38]. This latter possibility merits serious consideration since, as mentioned above, benzoate can increase the activity of the NMDA receptors the brain and—at high levels—might even cause abnormally low levels of glycine in the central nervous system. Furthermore, a small number of children are reported to develop asthma [39] or allergy [40] in response to dietary sodium benzoate.
To date, these detrimental effects have not been described for dietary potassium sorbate. This does not mean that potassium sorbate should necessarily be regarded as completely safe. Benzoate and sorbate are both disruptive to the structure of biological membranes [41,42], a property that allows them to impact on mitochondrial energy coupling in living cells. In model organisms, they cause appreciable increases in oxidative stress, the associated damage to mitochondria possibly contributing to the pathophysiology of mitochondrial disease [37,43]. Both additives are reported to contribute to the activation of inflammatory pathways in liver tissue [44]. Potentially, therefore, these preservatives might be risk factors in the development of several chronic diseases. Nevertheless there is no evidence to indicate that the benzoate or sorbate preservatives in beverages are a risk factor in diabetes [8]. It should be noted however that studies on yet another small monocarboxylic acid—the antiepileptic drug sodium valproate—have revealed that certain individuals can be rendered particularly susceptible to the harmful effects of this kind of agent through genetic disease or chronic medical conditions. These medical conditions might also sensitise individuals to any harmful effects of a high benzoate or sorbate intake (reviewed in [8]). To counteract this latter possibility, it may soon be possible to use DNA profiling to advise individuals on whether they might potentially be at risk from these—and other—dietary additives.
It is the relatively high resistance of spoilage yeasts to growth inhibition by benzoate and sorbate that imposes the need for relatively high levels of these preservatives in many beverages [42,45]. It is to be hoped that industry will support research into furthering our understanding of this resistance, thus providing the knowledge base that will allow them to use the lowest levels of preservative in their products that still ensure a long shelf life.
Official link to article: Piper, P.W. Potential Safety Issues Surrounding the Use of Benzoate Preservatives. Beverages 2018, 4, 33. https://doi.org/10.3390/beverages4020033