What Is the Skin Barrier?
Human skin consists of two main layers: the epidermis and the dermis. Of these, the epidermis is the outermost layer and can be further divided into five sublayers. The very top of the epidermis is called the stratum corneum, also known as the horny layer. This layer forms the skin’s barrier and plays a crucial role in protecting against external stressors while preventing the loss of moisture and other beneficial substances from the skin.
The stratum corneum is mainly made up of flat, overlapping corneocytes (dead skin cells) and an intercellular matrix of lipids (fats). The most important lipids in this layer are ceramides, cholesterol, and various fatty acids, which together form the skin’s permeability barrier.
Simply put, the structure of the stratum corneum can be compared to a brick wall, where the corneocytes are the “bricks” and the lipids are the “mortar” that holds them together.
Why Is an Intact and Functional Skin Barrier Important?
The skin barrier works in both directions—it prevents harmful substances from entering from the outside and also stops internal moisture from escaping. A healthy skin barrier protects the skin from bacteria, viruses, allergens, air pollution, and mechanical stress. When the barrier is intact, the skin feels smooth and soft without redness or flakiness. Even small disruptions in the stratum corneum can lead to various skin problems. A damaged barrier also makes the skin more vulnerable to UV radiation from the sun.
What Are the Symptoms of a Damaged Skin Barrier?
A damaged skin barrier is often recognized by redness, flakiness, and itchiness. You may notice breakouts, and products that previously worked well can suddenly start to sting or irritate. The skin may become oily more quickly—or, conversely, feel dry and tight—or even both at once!
What Causes Damage to the Skin Barrier?
A damaged skin barrier is often caused by products that are too harsh for your skin type, overuse of active ingredients, excessive exfoliation, or environmental conditions.
For example, brightening, cleansing, or exfoliating products often contain AHA or BHA acids. When these are combined for example with a vitamin C serum and a retinol-based night cream, it can be “too much” for the skin, often leading to barrier damage.
Weather conditions also affect how our skin functions. In Finland, the climate is highly variable, especially in winter—cold and dry air puts the skin under stress. Dry air increases moisture loss and disrupts the function of the stratum corneum.
When the skin barrier is damaged, protecting the skin and restoring its balance is key. Red, irritated skin benefits from soothing and anti-inflammatory ingredients. The CBD used in Blank& products is calming, moisturizing, anti-inflammatory, and antioxidant—making it ideal for repairing a damaged skin barrier. Blank& CBD facial oils, Evie and Amio, are excellent for protecting the skin; the carefully selected natural oils together with CBD nourish and calm the skin while forming a protective layer that locks in moisture and prevents dryness.
Read more about CBD here
Further Reading
