What is the toxicity of Vitamin E on the skin?

Essential to the body, vitamin E is primarily stored in the skin, both in the dermis (sebaceous glands) and in the epidermis (sebum). In cosmetic products, depending on its concentration, vitamin E is used as a preservative and/or antioxidant active ingredient. Indeed, it prevents premature skin ageing by limiting the harmful attacks of free radicals induced by sunlight and pollution. Moreover, it forms a protective film on the skin's surface, reducing dehydration.

Vitamin E actually refers to a group of eight fat-soluble molecules (which dissolve in fats): 4 tocopherols and 4 tocotrienols. For reasons of stability, alpha-tocopherol is the most common form of Vitamin E used in beauty care.

Note: In cosmetic formulations, vitamin E can be of synthetic origin (derived from petrochemicals) or natural. At Typology, the vitamin E is 100% plant-based; it is extracted from sunflower seed vegetable oil.

As a preservative, Vitamin E is effective from 0.02%, and it is recommended up to 0.2%. As an active ingredient, it is often introduced at a concentration ranging from 0.1 to 0.5%.

In 2014, the CIR (Cosmetic Ingredient Review) body concluded that tocopherol (concentration of 5% or less) is safe for use in skincare, as well as 13 of its other derivatives.

The thirteen derivatives in question can be identified on the I.N.C.I. lists of products under the following names: ascorbyl tocopheryl acetate, ascorbyl tocopheryl maleate, dioleyl tocopheryl, methylsilanol, potassium ascorbyl tocopheryl phosphate, sodium tocopheryl phosphate, tocophersolan, tocopheryl acetate, tocopheryl linoleate, tocopheryl linoleate/oleate, tocopheryl nicotinate tocopheryl phosphate tocopheryl succinate, tocotrienols.

Why do some brands use derivatives of Vitamin E? This is often related to a matter of cost and stability within the formula, in relation to the other ingredients present.

On the market, it is possible to find pure Vitamin E. However, caution is advised as it needs to be diluted to prevent any skin discomfort. Indeed, excessive dosages of tocopherol (>0.5%) can trigger skin irritation or sensitisation reactions. This can also accelerate oxidation processes. Generally, it is recommended to mix a few drops of Vitamin E into carrier oils to prevent them from becoming rancid, while simultaneously protecting the skin and hair from free radicals.

This fat-soluble vitamin should be stored in an airtight container, at room temperature, protected from oxygen, heat and light.

• Cosmetic ingredient review: Safety assessment of tocopherols and tocotrienols as used in cosmetics (2014).

• HASSAN I. & al. Vitamin E in dermatology. Indian Dermatology Online Journal (2016).