Subtitle: The Role of Barrier Support and TEWL Reduction in Cosmetic Science
Sensitive Skin Formulation: How to Reduce TEWL and Support the Skin Barrier
Learn how to formulate skincare for sensitive skin by understanding barrier repair, lipid balance, and trans-epidermal water loss (TEWL) reduction.
Introduction
Sensitive skin is more than a marketing term — it’s a clinically relevant skin type that affects product formulation at every stage. Designing skincare that supports the barrier, reduces inflammation, and respects the skin’s pH is essential for long-term tolerance and efficacy.
At SKD Pharmaceuticals, we specialise in barrier-friendly, clinically aligned formulations that support even the most reactive skin types.
1. Understanding the Skin Barrier
The stratum corneum — the outermost layer of the skin — acts as a barrier against water loss, irritants, and microbes. It contains:
- Corneocytes (dead skin cells)
- Lipid matrix (ceramides, cholesterol, free fatty acids)
When disrupted, the skin becomes dry, red, flaky, and more reactive — common signs of sensitive skin.
2. What Is TEWL and Why Does It Matter?
TEWL = Trans-Epidermal Water Loss
This is the amount of water that passively evaporates through the skin. Elevated TEWL indicates a compromised barrier and leads to:
- Dehydration
- Tightness
- Flaking or irritation
- Inflammatory signalling
Reducing TEWL is a cornerstone of sensitive skin formulation.
3. Key Ingredients to Support Barrier Function
| Ingredient | Function |
|---|---|
| Ceramides (NP, AP, EOP) | Restore lipid balance in stratum corneum |
| Squalane | Emollient that mimics natural sebum |
| Panthenol | Soothes and improves skin hydration |
| Oat Extracts (Avena Sativa) | Anti-inflammatory and calming |
| Niacinamide | Reduces TEWL and improves elasticity |
4. Avoiding Common Irritants
To reduce risk of reactions, avoid:
- Harsh surfactants (e.g. SLS)
- Strong acids in leave-on products
- Alcohol denat
- Essential oils and synthetic fragrances
- Sensitising preservatives (e.g. methylisothiazolinone)
5. Designing for Long-Term Tolerance
- Use mild emulsifiers (e.g. cetearyl olivate/sorbitan olivate)
- Ensure physiological pH (~4.7–5.5)
- Conduct repeat insult patch testing (RIPT) for claim support
- Offer fragrance-free and allergen-low options
6. SKD’s Sensitive Skin Product Lines
We offer full private label support for sensitive-skin ranges:
- Simpler Skin – Gentle, minimalist formulas
- VeenoDerm – Oat-powered skincare for barrier support
- EX65 – Emollient-rich products with extracellular matrix focus
Conclusion
Formulating for sensitive skin is a scientific discipline — and one that’s central to SKD’s clinical skincare development. If you’re building a brand that puts skin health first, barrier support and TEWL reduction must be at the heart of your formulation.