What is it?
A cleansing and emulsifying ingredient made by joining lauric acid, a fatty acid abundant in coconut oil, with lactic acid, and forming the sodium salt. It helps oil and water mix and helps lift away dirt, and it is used in face and body cleansers, lotions, creams and hair products. Despite the similar name, it is not sodium lauryl sulfate: it contains no sulfate.
Key information
- The CIR Expert Panel concluded in 2019 that sodium lauroyl lactylate is safe in cosmetics when formulated to be non-irritating and non-sensitizing.
- It is made from lauric acid and lactic acid and contains no sulfate, so it is not a form of sodium lauryl sulfate.
- It was a weak skin sensitizer in animal tests, and its close relative sodium stearoyl lactylate is permitted by the FDA as a food additive in baked goods.
More information
Lactylates are made by joining a fatty acid to two units of lactic acid and forming a sodium or calcium salt. The fatty acid forms an oil-loving tail and the lactylate a water-loving head, which is why they work as emulsifiers and cleansers. The Cosmetic Ingredient Review (CIR) reported 226 uses of sodium lauroyl lactylate in 2019, about evenly split between leave-on and rinse-off products, at up to 10 percent in skin cleansers and up to 6.1 percent in body and hand products.
The CIR Expert Panel reviewed it with nine related lactylates. At 10 percent it did not irritate rabbit skin, and undiluted it caused mild conjunctivitis in half of the rabbits tested and was classed as a non-irritant to the eyes. In animal allergy tests it was classified as a weak sensitizer, so the Panel concluded that lactylates are safe when formulated to be non-irritating and non-sensitizing, which may be based on a quantitative risk assessment. The Panel also pointed to the long use of lactylates as food additives without reported problems: the FDA permits sodium stearoyl lactylate in foods such as baked goods, pancakes and coffee cream substitutes.
Reality check: sodium lauroyl lactylate is not sodium lauryl sulfate (SLS). SLS is a sulfate detergent that the CIR describes as an irritant in patch tests at 2 percent and above and limits to 1 percent in products that stay on the skin. This ingredient has no sulfate group and is not ethoxylated, so it is not among the ingredients the FDA links to 1,4-dioxane. On labels, “lauroyl lactylate” is this ingredient, while “lauryl sulfate” is SLS.
Sources: Cosmetic Ingredient Review: Safety assessment of alkanoyl lactyl lactate salts (2019); Cosmetic Ingredient Review: Sodium lauryl sulfate and sodium laureth sulfate safety summary; Legal Information Institute: 21 CFR 172.846, Sodium stearoyl lactylate; FDA: 1,4-Dioxane in cosmetics, a manufacturing byproduct
