The Lipid Bilayer of the Stratum Corneum
The Lipid Bilayer of the Stratum Corneum — the layered arrangement of fatty molecules that fills the spaces between cells in the skin's outermost layer, forming a water-resistant seal. Often compared to mortar between bricks, it is essential for retaining moisture and keeping out irritants.
Key points
- The bilayer is composed mainly of ceramides, cholesterol, and free fatty acids arranged in ordered sheets.
- This lipid matrix acts as the primary barrier that limits water loss and blocks external irritants and allergens.
- A balanced ratio of ceramides, cholesterol, and fatty acids is important for the barrier to function properly.
- Harsh cleansing, over-exfoliation, and environmental stress can deplete these lipids and weaken the barrier.
Frequently asked
Why are ceramides important in moisturizers?
Ceramides are a major component of the skin's lipid barrier, so replenishing them can help restore the seal that retains water and protects against irritants.
What damages the skin's lipid barrier?
Frequent use of harsh soaps, hot water, over-exfoliation, and environmental stressors can strip these lipids, leading to dryness, sensitivity, and increased water loss.
Related topics
This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.
