When Winter Asks More of the Skin

Each winter, many people notice the same change. Skin feels tighter, drier and more reactive than it did only a few months earlier.

This isn't simply because the weather is colder. Winter changes the environment surrounding the skin, increasing the rate at which water naturally evaporates from its surface. This process is known as trans-epidermal water loss (TEWL).

From a corneotherapeutic perspective, healthy skin isn't achieved by forcing more hydration into the skin. It begins by supporting the skin barrier so it can better retain the hydration already within it.

What Is Trans-Epidermal Water Loss?

Water is constantly moving through the skin and naturally evaporating from its surface. This process, known as trans-epidermal water loss, is a normal and essential part of healthy skin function.

The goal is not to prevent TEWL entirely. Rather, it is to minimise excessive water loss while maintaining a healthy, resilient barrier.

When TEWL increases, the skin loses moisture faster than it can replenish it. The result is skin that feels tight, dehydrated, rough or more sensitive than usual.

A Simple Way to Think About It 

Imagine placing a glass of water on a windowsill. Over time, the water slowly evaporates into the surrounding air. Now imagine adding a thin layer of oil across the surface. The water beneath remains for longer because the oil slows evaporation.

Our skin behaves in much the same way. Facial oils don't add water to the skin. Instead, they help reduce excessive water loss by reinforcing the skin's natural lipid barrier.
In doing so, they help the skin retain the hydration already within it.

Why Winter Increases Water Loss

Winter creates the perfect conditions for increased TEWL. Cold air naturally contains less moisture than warm air, creating a greater gradient between the water held within the skin and the surrounding environment. Water is therefore lost more readily.

Other environmental factors compound this effect:

• Lower humidity
• Cold wind exposure
• Indoor heating and air conditioning
• Long, hot showers
• Frequent cleansing or over-exfoliation

Together, these factors place greater demand on the skin barrier, making it more difficult for the skin to maintain hydration and resilience.

Why Oils Become More Important in Winter

One of the skin barrier's primary functions is to reduce unnecessary water loss. This barrier is largely made up of lipids—ceramides, cholesterol and free fatty acids—which help create a protective seal over the skin. Facial oils complement this natural system by reinforcing the skin's surface and slowing evaporation.

This is why oils often become particularly valuable during winter. They don't replace the skin barrier; they support it.

When layered over humectants and moisturisers, they help keep hydration where the skin needs it most. 

Choosing Oils That Work With the Skin

Not all oils behave in the same way. Within corneotherapy, preference is given to
skin-compatible lipids that work in harmony with the barrier rather than simply creating a heavy occlusive layer.

Ingredients such as jojoba, squalane, moringa, camellia and rosehip are valued for their ability to nourish the skin while supporting barrier function.

The goal isn't simply to make the skin feel softer for a few hours. It is to improve the environment in which healthy skin can function.


Our Winter Edit

Thoughtfully formulated to support barrier function and minimise trans-epidermal water loss, these are the facial oils we return to throughout winter.

Prologic Skin Recovery Treatment Oil ($101)
MARYSE Omega Treatment Oil ($84)
Biode Daily Oil with Phyto-Nutrients ($49)