Vitamin E: Can we classify it as a preservative?

According to the European Regulation n°1223/2009 of the European Parliament and Council pertaining to cosmetic products, a preservative is defined as "a substance exclusively or primarily intended to inhibit the growth of micro-organisms in the cosmetic product". From this definition, it is understood that a preservative must possess a certain antimicrobial activity. The preservatives authorised in cosmetic care are all listed in Annex V of this regulation, also specifying in which type of product they can be incorporated and in what quantity.

Indeed, most cosmetic formulations, due to their high water content, are products that can easily be degraded by microorganisms. Microbial contamination of cosmetics represents a significant risk to consumer health as it can lead to irritations, inflammations or allergies, particularly when they are applied to damaged skin, around the eyes or on the skin of babies. Hence the essential role that preservatives play. However, it should be noted that not all preservatives are equal and some may pose a risk to human health or the environment. That's why Typology has decided to exclude certain ones, as a precautionary principle, such as methylisothiazolinone and phenoxyethanol.

Note : Consumers also play a role in the proper preservation of their cosmetic product. Adhering to the use-by dates, periods after opening, storing the products in a cool, dry place away from light, and regularly checking their organoleptic properties (colour, texture, smell...) are among the key behaviours to adopt.

The vitamin E is a naturally occurring fat-soluble substance, meaning it is soluble in fatty substances. It is an essential nutrient for the body, but not produced by it. A very popular cosmetic active, vitamin E is especially recognised for its antioxidant properties. Indeed, its aromatic chemical structure allows it to easily donate an electron to free radicals, without losing its stability. In the skin, vitamin E is predominantly found in the stratum corneum and in sebum, where it ensures, along with coenzyme Q10, the protection of its constituents from lipid peroxidation. It fulfils a similar function in vegetable oils, which are also sensitive to the oxygen in the air and UV rays. Vitamin E is sometimes added to oily formulations for this purpose, earning it the nickname of "natural preservative".

However, despite the benefits it offers for the preservation of oils, vitamin E does not possess any antibacterial properties and cannot prevent microbial contamination of aqueous phases. Moreover, it is not listed in Annex V of the European Cosmetic Regulation.

Vitamin E cannot thus be considered as a preservative, in the strictest sense of the term.

• Regulation (EC) No 1223/2009 of the European Parliament and the Council.

• GARCIA-JARES C. & al. Preservatives in Cosmetics: Regulatory Aspects and Analytical Methods. Analysis of Cosmetic Products (2018).