Winter Xerosis: Why does skin become drier in winter?

When temperatures drop and the air becomes drier, the skin is put to a severe test. Designed to act as a barrier, it must constantly adapt to changes in its environment. Winter imposes specific challenges: between the cold, wind, decreasing humidity, and indoor heating that dries out the air, the skin's balance is compromised. The result: the transepidermal water loss (TEWL) of the skin increases, its surface becomes rougher and feelings of discomfort set in. When this dryness becomes very significant, it is referred to as xerosis. This phenomenon is based on several factors that impair the skin's ability to maintain its hydration.

One of the initial effects of cold on the skin is the reduction in lipid production. To recall, the skin is composed of three layers: the epidermis, the dermis, and the hypodermis. The outermost layer, the epidermis, is further divided into four layers, including the stratum corneum, located on the surface. Between the corneocytes, the cells of the stratum corneum, are lipids, such as ceramides, cholesterol, and free fatty acids, which seal the cells together and prevent the evaporation of water. This evaporation is also limited by the hydrolipidic film, a mixture of sweat and sebum that covers the skin.

Indeed, when temperatures drop, blood vessels tend to contract: this is referred to as vasoconstriction. To preserve the warmth of vital organs, such as the heart and lungs, the body reduces blood flow to the skin, which slows down the supply of oxygen and essential nutrients for the production of sebum and epidermal lipids. With fewer ceramides to ensure cellular cohesion and a weakened hydrolipidic film, the skin becomes more permeable and water evaporates more easily. This mechanism is amplified by the humidity of the outdoor air, which significantly decreases in winter. The water contained in the skin then escapes into the surrounding air. The drier the air, the faster this evaporation occurs, thus accelerating skin dehydration. Moreover, the wind, often strong in winter, exacerbates this process by sweeping away the hydrolipidic film.

Finally, beyond these biological phenomena, certain daily habits contribute to worsening winter xerosis. Hot showers and baths, although comforting during this season, tend to dissolve the lipids in the epidermis, further weakening the skin barrier. Similarly, heating systems significantly dry out the surrounding air, intensifying the skin's water loss.

Winter xerosis results from an increased loss of water through the skin, primarily caused by cold, wind, and a decrease in ambient humidity.

To mitigate winter xerosis, we recommend adopting a skincare routine that combines hydration and protection. More than just comfort, the daily application of a cream or balm rich in humectants, such as hyaluronic acid or glycerin, emollients, like ceramides, and occlusives, like shea butter, becomes essential to restore the skin barrier and prevent water loss. For instance, you could opt for our lipid-replenishing balm, suitable for both facial and body skin. Formulated with 99% natural ingredients, it extends the periods between severe dryness and provides continuous hydration for 24 hours.

Another recommendation to prevent winter xerosis: favor gentle cleansers and avoid overly hot showers. Indeed, some cleansing products contain sulfates, surfactants with strong cleaning power, but also known for their potential to irritate. However, skin weakened by xerosis needs gentleness and lipid-replenishing cleansing care, like our lipid-enriched cleansing bar for example. Suitable for sensitive and atopic-prone skin, this care product formulated at the physiological pH of the skin gently cleanses and soothes feelings of tightness. Free of sulfates, it contains calendula extract, sweet almond oil, and shea butter, natural ingredients recognized for their effectiveness in cases of xerosis.

Winter puts the skin through a tough test, but a suitable skincare routine can prevent xerosis and maintain soft and comfortable skin, even in freezing weather.