Hair Nourishment: Part 1 of 3 - What is Hair
Under the hair butters post, I had an intriguing discussion with Keisha and an anonymous commenter about 'nutrients' for hair and whether unrefined butter is actually better than refined. In the process of getting a good answer, it occurred to me that I should actually define what hair is. Here is the science. Hair is made within the follicle (inside the scalp) and the follicle is the ‘living’ part of hair. The cells that make up the hair do eventually 'die' as they loose their nucleus (in essence the nucleus is the brain of the cell that directs it to do what it does). Despite the simplicity of this process, hair is actually a feat of engineering. It has an internal shaft (hair shaft) which is made up of strong fibres and protecting all of this are the thin scales known as the cuticle. Each cuticle is made up 4-6 layers.
The cuticle is really the equivalent of the roof on a building. The only thing preventing water from above from soaking through the wood/stone and brick of your house is the roof. The roof also keeps in heat and blocks out cold. This is the same way that the cuticle works. It blocks moisture from leaving the hair shaft. It also slows down entry of substances (water/oils/conditioning agents) and it protects the shaft from damage (many times when strength testing, the cuticle will rupture before the shaft does - therefore the cuticle is protecting the shaft by taking the force first). So now that the structure of hair is known, it is time to answer the big question, Can you nourish hair? Does hair require nourishing given that it is technically dead, is this really possible?
Tune in tomorrow for Part 2 of 3 : Can you nourish hair? References for the hair structure information above Chemical and Physical Behaviour of Hair – Clarence Robbins Forensic Examination of Hair – James Robertson