How to Avoid Skin Water Loss?

Hydrated skin isn’t just about how much water you drink. It’s about keeping that water from escaping your skin in the first place. This process, known as transepidermal water loss (TEWL), plays a key role in skin dryness, sensitivity, and premature aging.

So how do you protect your skin from losing moisture?

What Is Transepidermal Water Loss?

TEWL refers to the natural evaporation of water through the outermost layer of the skin. While this is a normal function, excessive TEWL means your skin is losing more water than it can retain. The integrity of the skin barrier is the most critical factor in controlling water loss.

1. Strengthen the Skin Barrier

Your skin’s barrier (stratum corneum) is made up of skin cells surrounded by lipids like ceramides, cholesterol, and fatty acids. When this layer is damaged, water can escape more easily. Moisturisers containing ceramides, niacinamide, and essential fatty acids have been clinically shown to restore barrier function and reduce TEWL.

2. Use Occlusive Ingredients

Occlusives create a physical seal over the skin to trap moisture and prevent evaporation. Petrolatum, for example, is known to reduce water loss by more than 98%. Other effective occlusives include squalane, shea butter, and dimethicone. These ingredients are particularly effective when used as the final step in your evening skincare routine.

3. Layer Smartly: Humectants, Emollients, Occlusives

To truly retain hydration, it helps to layer three types of ingredients:

• Humectants (like hyaluronic acid or glycerin) draw water into the skin

• Emollients (such as plant oils or esters) smooth and soften skin texture

• Occlusives lock in moisture and prevent evaporation

This combination mimics your skin’s natural protective structure and helps maintain hydration over time.

4. Avoid Over-Cleansing

Cleansing too frequently or with harsh surfactants can strip away the natural oils that form part of your barrier. Opt for a gentle, pH-balanced cleanser and avoid hot water, which can increase TEWL by disrupting the lipid layer.

5. Environmental Stressors

Cold weather, indoor heating, low humidity, and UV exposure all increase water loss from the skin. Using a daily SPF and maintaining a well-humidified environment during winter months can make a noticeable difference.

Preventing water loss isn’t just about moisturizing. It's about supporting your skin’s ability to hold on to water. Focus on strengthening the skin barrier, using moisturepkeeping ingredients, and avoiding habits that destroy your skin’s natural defenses. With the right strategy, you can ensure skin longevity by keeping it moisturised.

Best wishes, 
Dr. Kat Molenda