The Skin’s Water Pathways – Aquaporins and TEWL

Water balance within the skin is one of the most fascinating and important topics in cosmetic science. It’s what keeps our skin soft, elastic, and healthy, and when disrupted, it can lead to dryness, irritation, and barrier damage. In this educational resource, we explore two key mechanisms that regulate how water moves in and out of the skin: Aquaporins and Transepidermal Water Loss (TEWL).

Aquaporins act as microscopic water channels that allow the controlled movement of water and small molecules like glycerol through skin cells. They help maintain deep, internal hydration within the epidermis. TEWL, on the other hand, is the natural process of water evaporating from the surface of the skin, something we can measure to assess barrier strength and hydration balance.

When these two systems are in sync, the skin remains hydrated, resilient, and radiant. But when either one is compromised, moisture loss increases and the skin begins to feel tight, flaky, or irritated.

This PDF takes a deep dive into the science behind these pathways, explaining how aquaporins work, what causes TEWL to increase, and how cosmetic formulations can be designed to protect and support both. Whether you’re a beginner formulator or a professional looking to refresh your knowledge, this resource will help you understand the vital connection between cellular hydration and barrier protection.

Download your copy now to strengthen your understanding of how the skin truly manages its water balance, from within and at the surface.