Transepidermal water loss (TEWL) is a term used to describe the amount of water that evaporates through the skin. This essential process helps regulate body temperature and maintain the skin’s hydration levels. However, when the skin’s natural barrier function is compromised, excessive TEWL may occur, leading to dry, dehydrated, and irritated skin.
Skin Barrier Function
The skin is the largest organ in the body and acts as a protective barrier between the internal and external environments. The outermost layer of the skin, called the stratum corneum, is responsible for preventing water loss and protecting the body from harmful environmental factors such as UV radiation, pollution, and bacteria.
The stratum corneum is composed of keratinocytes, which produce a mixture of lipids and proteins that help to maintain the skin’s barrier function. These lipids, also known as ceramides, form a protective barrier that prevents excessive water loss and maintains the skin’s hydration levels.
Factors That Affect Skin Barrier Function
Several factors can affect the skin’s barrier function, leading to increased TEWL and dry skin.
Age is one of the most significant factors that can affect the skin’s barrier function. Aging causes the skin’s natural barrier function to weaken, leading to increased TEWL and dry skin. The skin’s reduced ability to produce essential lipids, such as ceramides, decreases with age, leading to a compromised barrier function.
Environmental factors such as cold, dry air, and low humidity can also affect the skin’s barrier function. Exposure to harsh environmental conditions can strip the skin of its natural oils, leading to increased TEWL and dryness.
Skin disorders such as eczema, psoriasis, and rosacea can also affect the skin’s barrier function. These conditions can cause inflammation and damage to the skin.
Finally, skincare products can also affect the skin’s barrier function. Certain products, such as those containing alcohol or harsh chemicals, can strip the skin of its natural oils.
Improving Skin Barrier Function
Effective moisturizing is one of the most effective strategies for improving skin barrier function. Using a moisturizer that contains ingredients such as ceramides, glycerin, and hyaluronic acid can help to restore the skin’s natural barrier function and reduce TEWL. Moisturizers work by forming a protective barrier on the skin’s surface, preventing excessive water loss and helping to maintain the skin’s hydration levels.
Avoiding harsh skincare products is another essential strategy for improving skin barrier function. Choosing skincare products that are gentle and free from harsh chemicals can help to protect the skin’s natural barrier function. Avoiding products that contain alcohol, fragrances, and other irritants can help to prevent further damage to the skin’s barrier function.
Using a humidifier can also help to improve skin barrier function by adding moisture to the air. Low humidity levels can lead to increased TEWL and dry skin, but using a humidifier can help to keep the air moist and prevent excessive water loss from the skin.
Additionally, protecting the skin from the sun is also crucial for maintaining healthy skin barrier function. UV radiation can damage the skin’s natural barrier function, leading to increased TEWL and dryness. Wearing a high SPF sunscreen and avoiding excessive sun exposure can help to protect the skin from UV radiation and prevent further damage to the skin’s barrier function.
Hydration Claims in Skincare Products
Validated Claim Support works with skincare and cosmetic providers to validate hydration claims in products by furnishing the scientific evidence needed to back them. As it pertains to hydration claims, providers should work with FDA registered third-party laboratories to conduct clinical studies to demonstrate the efficacy of their products in reducing TEWL. These studies involve measuring skin moisture levels before and after product use and utilizing validated methodologies to ensure accurate results. Validated Claim Support enables manufacturers and providers to promote a more trusting relationship with customers by delivering evidence-based claims and bolstering the credibility of their hydration assertions.
To learn more about how your skincare company can engage in hydration product testing, we encourage you to contact us today.
