Ceramides: Your Skin Barrier's Main Ingredient
Ceramides make up 50% of the outer skin barrier. What they are, how they work, and why replacing them with skincare products actually helps.
Your outer skin barrier is often compared to a brick wall. The "bricks" are dead skin cells; the "mortar" is a mixture of lipids — and ceramides make up roughly half of that mortar. When ceramide levels drop, the wall develops gaps: water escapes and irritants get in.
What happens when ceramides deplete
Age, harsh cleansers, over-exfoliation, low humidity, and genetic conditions like eczema all reduce ceramide levels. The symptoms are familiar: dryness, tightness, sensitivity, redness, and increased reactivity. Essentially, the barrier cannot do its job.
Ingredient spotlight — Ceramides
Lipid molecules that form the structural mortar of the skin barrier, preventing water loss and blocking irritant entry.
Good for
- Dry skin
- Eczema-prone skin
- Post-retinoid barrier support
- Sensitive or reactive skin
Use with caution if
- No known contraindications — ceramides are naturally occurring in skin
Do topical ceramides actually work?
Yes, with nuance. Topical ceramides are structurally similar to skin ceramides and integrate into the stratum corneum, reducing transepidermal water loss (TEWL). Multiple randomised trials show them improving dryness and eczema symptoms. They work best in combination with other barrier lipids — cholesterol and fatty acids — which is why good barrier creams include all three.
Knowledge check
0 / 2 correct1. What percentage of the outer skin barrier's lipid mortar is made of ceramides?
2. What does TEWL stand for, and why does it matter?
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