- An outer layer, the cuticle
- Under that lies the cortex
- And at the core lies the medulla
The cuticle is actually made up of layer upon layer of shingle-like or scale-like overlapping cells. 5 to 12 layers make up the cuticle surface. These layers are not visible to the naked eye.
- Hard and transparent
- Gives hair it's shine or glow
- Gives hair mechanical strength
The Hair Cuticle and Defence
The cuticle is the first line of defence against damage from heat, excessive brushing and chemicals.
When the hair cuticle incurs damage the layers become irreversibly lifted - they no longer lie flat along the surface.
Damage From Hair Color and Relaxer
Part of the reason hair can easily get damaged when you color or relax it is that the cuticle layer has to be lifted to let in the colour (or the relaxer) and then flattened back. It's very easy to for the layer to be lifted and then for it to fail to flatten again.
Every day environmental forces such as harsh sun or wind can also wear the cuticle down.
So there it is; the difference between healthy and unhealthy hair is the cuticle.