What Is Sodium Benzoate?
Sodium benzoate is the sodium salt of benzoic acid, a compound that occurs naturally in berries, cinnamon and certain fermented products. It appears as a white, water-soluble powder that has little scent on its own. First adopted by the food industry in the late 1800s to keep products fresh, it soon found a place in personal care formulas where the same spoilage concerns exist. The ingredient is typically made by combining benzoic acid with sodium hydroxide, a straightforward reaction that yields a stable, easy-to-handle powder.
Because it dissolves well in water and stays active over a broad pH range, sodium benzoate shows up in many water-based cosmetics such as facial cleansers, toners, gels, masks, shampoos, conditioners, moisturizers, baby wipes, sunscreens and makeup removers. Brands rely on it as a go-to option when they want a dependable preservative that pairs nicely with other common ingredients.
Sodium Benzoate’s Cosmetic Benefits/Uses
In skin and hair care formulas sodium benzoate serves several practical roles that help keep products safe, pleasant and long-lasting.
- Anticorrosive – Helps prevent metal components of packaging, pumps or caps from rusting which protects both the product and its container
- Fragrance – Contributes a mild sweet aroma that can round out a scent profile without overpowering other fragrance notes
- Preservative – Inhibits the growth of bacteria, yeast and mold which extends shelf life and allows brands to offer products that remain stable during everyday use
Who Can Use Sodium Benzoate
Thanks to its mild profile sodium benzoate suits most skin types including oily, normal and combination skin. Dry or very sensitive complexions usually tolerate it well too because the ingredient does not strip moisture or disrupt the skin barrier, though anyone with a known benzoic acid allergy should avoid it.
Sodium benzoate is synthesized from benzoic acid and sodium hydroxide, both mineral or petrochemically derived, so it contains no animal by-products. This makes it acceptable for vegans and vegetarians.
The compound is generally regarded as safe for people who are pregnant or breastfeeding when used in typical cosmetic concentrations. That said this is not medical advice and expectant or nursing users should consult a healthcare professional before adding any new product to their routine.
Sodium benzoate does not increase photosensitivity, so it will not make skin more prone to sunburn. It also plays nicely with most other cosmetic actives and does not interfere with SPF performance, antioxidants or exfoliating acids.
Potential Side Effects/Adverse Reactions
Reactions to topical sodium benzoate differ from person to person. The following list covers potential side effects, but most consumers will not encounter them when the ingredient is used at standard levels in well-formulated products.
- Mild skin irritation – transient redness or itching, primarily in very sensitive individuals
- Contact dermatitis – rare allergic response that can present as rash, swelling or burning
- Eye or mucous membrane sting – possible if a product gets into the eyes or is applied to broken skin
- Interaction with high levels of vitamin C – under extreme heat or UV exposure this pairing can form trace benzene, though cosmetic formulas are designed to keep concentrations far below safety limits
If you experience any of these issues stop using the product and seek guidance from a medical professional.
Comedogenic Rating
Rating: 0/5. Sodium benzoate is a small, highly water-soluble salt that does not linger on skin or mix with skin oils, so it has virtually no pore-clogging potential. It functions as a preservative rather than an emollient or fatty ingredient, which further limits any chance of forming comedones.
Suitable for acne-prone or breakout-prone skin, as it will not contribute to blackheads or whiteheads.
Most published comedogenicity lists do not even include sodium benzoate, which supports its reputation for being non-comedogenic.
Summary
Sodium benzoate works as a preservative, fragrance component and anticorrosive agent by dissolving rapidly in a water phase, lowering microbial activity and helping protect formulas and packaging parts from rust. Brands like it because it is inexpensive, easy to use in a wide pH range and compatible with many other ingredients, so it shows up in everything from cleansers to baby wipes.
The ingredient is generally viewed as safe for all skin types with only rare reports of irritation. Still, every skin is unique, so it is wise to patch test any new product that contains sodium benzoate to confirm personal tolerance.