What is TEWL – and why is your skin so thirsty?

When your skin feels dry, tight, or dull – even after moisturising – you may be dealing with more than just dryness. It could be a sign of dehydrated skin caused by something called trans-epidermal water loss (TEWL).

What is TEWL?

TEWL is the natural process where water escapes from the deeper layers of your skin and evaporates into the air.

Your skin is always losing a little water – that’s normal. But when your skin barrier is weakened, water escapes too quickly, leaving your skin depleted, tight, and unable to retain the moisture it needs to stay plump and healthy.

What causes TEWL?

Several factors can compromise your skin’s ability to hold onto water:

• Environmental stressors like cold air, wind, or sun exposure
• Harsh skincare products that strip away natural oils and damage your skin’s barrier
• Air conditioning or indoor heating that pulls moisture from the air
• Ageing, which naturally weakens the skin barrier over time

When the skin barrier is impaired, it’s like having cracks in a bucket – no matter how much water you pour in, it keeps leaking out.

Dehydration can affect all skin types – even oily or acne-prone skin. Look for these tell-tale signs:

• Skin feels tight or uncomfortable
• It looks flat and lacking in bounce
• Fine lines may look more visible (especially around the eyes or mouth)
• You may notice flaking, itching, or rough texture
• Your skin may overproduce oil to compensate, creating an imbalance.

The key to combating TEWL is not just to add water to your skin – but to help your skin hold onto it.

Draw moisture into the skin
Use humectants like hyaluronic acid and mānuka honey, which act like magnets to pull water into the upper layers of your skin.

We love Baptise Hyaluronic H₂O Ultra-Hydrating Water Gel, packed with mānuka honey and naturally sourced plant hyaluronic acid for enduring hydration. Sustainable harakeke flax gel combines with mamaku black fern to help revitalise and protect the skin.

Strengthen your skin barrier
Natural ceramides and nourishing oils (like kiwi seed oil) help reinforce your skin’s lipid barrier – sealing the surface and preventing water from escaping.

Lock in hydration
Occlusive botanicals, such as bamboo ferment, create a breathable layer on the skin’s surface that traps moisture where it’s needed, protecting against environmental water loss.

We love Maya Hyaluronic 72-Hour Hydration Serum, a thirst quencher for dry and dehydrated skin, enriched with plant hyaluronic acid, high-performance Pheohydrane and bamboo ferment to attract and retain water to foster a dewy complexion.

Avoid harsh, stripping products
Choose gentle, pH-balanced skincare that doesn’t disrupt your natural protective barrier.

We love Hallelujah Lime & Patchouli Nourishing Cleanser – our original cream cleanser that gently clears impurities without stripping the skin.