Vitamin B12, an ally for dry skin?

Relatively thin, a dry skin is fragile, sensitive and often prone to redness and feelings of tightness. This type of skin lacks flexibility and can thus seem rough to the touch. Although the confusion is easy, a dry skin is different from a dehydrated skin : the former is a permanent situation characterised by a low production of sebum and a deficiency in lipids in the horny layer, while the latter is a temporary state distinguished by its need for water and hygroscopic substances.

A dry skin requires nourishing actives such as squalane, ceramides, or even vegetable oils.

Vitamin B12 is a water-soluble molecule synthesized exclusively by certain bacteria. It is essential for the proper functioning of the human body and its intake is ensured by diet. Vitamin B12 also plays a role in cosmetics: as an anti-inflammatory, it has shown its usefulness in various studies for conditions such as eczema and psoriasis, which are inflammatory skin diseases. From a mechanistic point of view, it is assumed that this vitamin inhibits the synthesis of nitric oxide (NO), a molecule that stimulates the proliferation of keratinocytes in the epidermis, as well as vasodilation, and consequently, the erythema and edema that weaken the skin barrier. Thus, vitamin B12 could have an interesting indirect epidermal structural role for dry skin.

Furthermore, several studies seem to indicate that vitamin B12 may have antioxidant properties. While the exact mechanism is still under investigation, it is suspected that this active ingredient would stimulate the trapping of free radicals by protecting glutathione, an antioxidant enzyme naturally found in the body. This property, important regardless of skin type, is particularly interesting for people with dry skin. Indeed, oxidative stress destabilises the skin's barrier function, which is already weakened in dry skin. By promoting the elimination of free radicals, vitamin B12 provides a certain level of protection to the skin.

Apart from these two indirect effects, vitamin B12 does not appear to provide any specific benefits to dry skin.

Did you know? In solution, vitamin B12 exhibits a lovely pink hue, thus lightly tinting the cosmetics it is incorporated into. This colour is derived from its chemical structure, which consists of a core with a central cobalt atom.