Article Overview
- Trans-epidermal water loss (T.E.W.L.) refers to the evaporation of moisture from the skin, which can lead to dehydration and skin barrier weakness.
- Factors such as age, environmental aggressors, and skincare habits can contribute to T.E.W.L.
- To minimize T.E.W.L. and maintain skin hydration, it is important to incorporate humectant and occlusive ingredients into your skincare regimen.
- Humectants attract moisture to the skin, while occlusives act as a barrier to minimize T.E.W.L. and protect against environmental aggressors.
- Ingredients like hyaluronic acid, glycerin, urea, and vitamin B5 are effective humectants, while fatty acids and vegetable-derived oils are beneficial occlusives.
What is Trans-epidermal Water Loss?
Though the term is more likely to be used in a professional setting than a casual conversation, trans-epidermal water loss (TEWL) is simply medical speak for when moisture evaporates from the skin and leads to dehydration.
To understand trans-epidermal water loss, imagine that the uppermost layers of the skin (the stratum corneum and epidermis) are a brick wall. Dead skin cells are the bricks and the lipids surrounding the cells are like the mortar that holds everything together. If there are cracks in this brick wall, moisture can leak out and irritants can make their way in. TEWL is a measure of the water that escapes through the skin barrier.
Research has shown that higher trans-epidermal water loss may be a sign of skin barrier weakness. (Conversely, lower TEWL may be associated with a stronger skin barrier.) The moisture loss associated with TEWL can cause fine lines and wrinkles to appear more prominent and lead to a dull, lackluster skin appearance. Essentially, TEWL leads to dehydrated skin.
What Causes TEWL?
The skin has three main layers. The epidermis is the outermost layer, the dermis is the middle layer, and the hypodermis is the deepest layer. Trans-epidermal water loss occurs when water travels from the dermis to the epidermis and evaporates from the skin’s surface. TEWL is a natural process, but factors that impair the skin barrier’s function can increase TEWL.
TEWL can be affected by age and vary depending on the area of body. Since TEWL is linked to skin barrier health, it may also be affected by environmental aggressors like low humidity, pollution, UV rays, and other sources that generate environmental stressors.
Skincare habits such as over-exfoliation, under-moisturizing, using harsh skincare ingredients, and even professional procedures can disrupt the skin barrier and contribute to trans-epidermal water loss.
The Role of Skincare in TEWL
The proper skincare products for dehydrated skin can help minimize trans-epidermal water loss by keeping the skin hydrated and moisturized.
To minimize trans-epidermal water loss and maintain skin hydration, it’s important to incorporate humectant and occlusive ingredients into your skincare regimen. Humectants help attract moisture to the epidermis, either from the air if there’s enough humidity or from lower layers of the skin if there’s not.
Transferring moisture from one layer of the skin to another is less than ideal, and this is where occlusive ingredients come in. When combined with humectants that create a moisture reserve within the skin, occlusives act as a barrier on the skin’s surface that helps minimize TEWL. At the same time, occlusive ingredients also help prevent environmental aggressors like pollution, irritants, and microbes from entering the skin.
In essence, skincare can help reduce trans-epidermal water loss by supplementing the skin with moisture and reinforcing the skin’s barrier so it stays put. Humectant ingredients to look for include hyaluronic acid, glycerin, urea, and vitamin B5. Among the most effective occlusive ingredients are fatty acids and vegetable-derived oils.
SkinCeuticals Solutions for TEWL
You can help prevent excess TEWL and protect the skin’s barrier by moisturizing frequently with products that contain humectants and occlusives. It’s more important to focus on integrating both of these types of ingredients into your skincare regimen as a whole rather than looking for formulations that include both. You can reap the benefits of humectants and occlusives, even if your skin gets them from different products.
Hydrating B5 Gel
Featuring moisture-attracting hyaluronic acid and vitamin B5 to promote barrier repair, this oil-free serum can be added to any skincare regimen for extra hydration or used as a stand-alone moisturizer for oily or blemish-prone skin.
Hydrating B5 Masque
This targeted mask helps restore the skin’s moisture balance by providing long-lasting hydration and optimizing skin-barrier function. Its advanced moisture complex includes a synergistic blend of ingredients that mimics the skin’s natural moisturizing factor.
SkinCeuticals Phyto products
Phyto Corrective Gel, Phyto A+ Brightening Treatment, and Phyto Corrective Masque all provide skin affected by TEWL with the hydration it needs along with a soothing blend of botanical ingredients.
Triple Lipid Restore 2:4:2
In addition to its powerful anti-aging benefits, this advanced moisturizer helps optimize the skin barrier with an optimal (and patented) ratio of ceramides, natural cholesterol, and fatty acids. The nourishing formula also improves the appearance of skin smoothness, laxity, pores, and overall radiance.
Epidermal Repair
Ideal for replenishing moisture and restoring the skin barrier after professional procedures, this cream soothes the skin and reduces visible redness. Always consult with your physician
C E Ferulic®
Since environmental aggressors can play a role in transepidermal water loss, this proven-effective daily vitamin C antioxidant helps prevent damage caused by pollution and UV rays that can compromise the skin barrier and promote TEWL.
To discover the ideal skincare routine that hydrates the skin, strengthens the barrier, and helps minimize transepidermal water loss, use our online Routine Finder, visit one of our SkinCeuticals SkinLab locations, or schedule an appointment with a SkinCeuticals Skincare Professional for a one-on-one consultation.
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