To understand the mechanism of lanolin’s action, it is worth looking at the structure of the stratum corneum.

The outermost part of the skin is composed of cells embedded in a lipid matrix often referred to as intercellular cement. This structure functions as the body’s natural protective barrier.

A healthy epidermal barrier limits water loss, protects against microorganisms, and reduces the skin’s susceptibility to irritants.

Damage to this structure leads to an increase in transepidermal water loss, abbreviated as TEWL (Transepidermal Water Loss). Consequently, dryness, roughness, a feeling of tightness, and increased susceptibility to irritation occur.

It is precisely in this area that lanolin plays a particularly important role.

Lanolin and transepidermal water loss (TEWL)

One of the best-documented effects of lanolin is the reduction of transepidermal water loss.

After application to the skin surface, it creates a flexible protective layer that slows down the process of moisture evaporation. Thanks to this, the hydration level of the epidermis improves, and the skin becomes softer and more elastic.

At the same time, the components of lanolin support the reconstruction of the skin’s natural lipid structures. This means that the moisturizing effect is not solely a result of surface action, but also of supporting the physiological mechanisms responsible for maintaining a proper protective barrier.

This is exactly why lanolin has been used for many decades in preparations designed for the care of dry, rough skin exposed to excessive moisture loss.

6.The epidermal barrier – the skin’s natural protective shield