Sensitivity Is Subjective
There are 5 generally agreed upon skin types in the skincare and cosmetics industries: normal, dry, oily, combination and sensitive. This classification system is somewhat flawed. We may readily understand what the terms oily and dry indicate, but “normal skin” is not a medical term and the concept of sensitive skin is subjective. Oily and dry skin could each, on their own, be seen as a sensitivity: one being prone to acne and breakouts and the other to flakey, red and itchy skin. The generally accepted definition within the realm of skincare and cosmetics formulation, however, identifies sensitive skin as having a high propensity for redness and irritation.
Sensitive Skin Has a Weakened Barrier
The epidermis consists of 5 sub-layers of keratinocyte cells. Keratinocytes are the most common type of skin cells. They make keratin, a protein that provides strength to skin, hair, and nails. These cells, produced in the innermost layer, migrate up towards the surface of the skin, maturing and changing as they become the next successive layer. Each layer of the epidermis has a function; they work together to limit the penetration of harmful substances and excess water loss. The stratum corneum, the outermost layer of the epidermis is made up of skin cells and oils that sit together like bricks and mortar. This brick wall acts as a permeable layer that defines the boundary of our body, keeping microscopic foreign substances out while also allowing the transfer of moisture and heat between the body and the outside world. This is often referred to as skin’s “barrier function.” Those with sensitive skin have a more permeable epidermis, making the skin more vulnerable to pathogens and allergens and making it harder for the skin to attract and retain moisture.
Sensitive Skin Can Happen to Anyone
When water passes from the inner layers through the epidermis and evaporates from the skin’s surface, this is known as transepidermal water loss (TeWL). TeWL is a process that your skin naturally regulates as a part of its barrier function. Some people’s skin may naturally tend toward dryness, their cells may be genetically programmed to retain less water. Other genetic factors can lead to sensitive skin conditions like eczema. These and skin injuries may require medical attention or pharmaceutical treatment, but other common and everyday factors such as low-humidity weather, wind, exposure to hot water, changes to the microbiome and topically applied products can impact TeWL. The truth is, dry skin can happen to anyone. When skin is dry, the cells can shrink, the edges may curl, leaving small cracks or space between them resulting in a weakened barrier that may result in sensitive skin.
Proper Skincare Can Help
While properly caring for sensitive skin can be time consuming and expensive, the good news is there is a lot you can do to effectively defend and protect your sensitive skin. These activities essentially reduce to moisturization and retention: adding moisture to the skin with water and humectant ingredients and keeping it in the skin by mimicking and reinforcing the skin’s natural barrier function with emollient and occlusive ingredients. If you have a sensitive skin condition, you will also want to treat any underlying causes with the help of a certified dermatologist. When Moisturizing: apply a thick layer of moisturizer all over your skin within three minutes of bathing or showering to lock in moisture and protect the skin barrier. Rather than drying fully with a towel, gently “pat dry” leaving skin moist before you moisturize. If you use a prescription topical medication, apply it as directed, before you apply moisturizer. Use a moisturizer specifically formulated for sensitive skin that omits known irritants and allergens (like lanolin, dye, fragrance, and harsh preservatives).