What is TEWL?
Transepidermal water loss (TEWL) is the natural process of water evaporating from the skin into the air. It is a normal part of skin function, but when it is too high, it can lead to dryness, irritation, and a weakened skin barrier.
Why It Matters
Skin dehydration – High levels of water loss means the skin loses too much water, making it feel tight, rough, or flaky.
Barrier damage – Excessive water loss can weaken the skin’s protective layer, leading to sensitivity and inflammation.
Premature ageing – A compromised barrier can make the skin more prone to fine lines and environmental damage.
How Skincare Can Help
Skincare products can strengthen the skin barrier and locking in moisture. Ingredients like ceramides, glycerin, hyaluronic acid, and fatty acids help trap water and repair the skin’s natural defences. Using moisturisers that contain both humectants (to attract water) and occlusives (to seal it in) is key.
How to Avoid It
High TEWL is common in conditions like eczema, psoriasis, and after overusing exfoliating acids or retinoids. If the barrier is damaged, harsh products can make it worse. Choosing gentle, barrier-supporting skincare is important when it is a concern.
