To better understand the properties of hair and its ins and outs, we’re offering a quick mini-lesson below—we are called All Things Hair after all, and it behooves us to keep you guys informed on your crowning glories from the inside out. Read on to find out more:
What Is Hair Made Of?
1. Keratin
According to Unilever’s Leon-van Gorkom, “Keratin filament proteins are found in all outer layers of human skin (stratum corneum) to protect the underlying cells. Your hair and nails also have keratin. However, nails also contain different keratin filament proteins for extra hardness and strength.” So to answer your question, hair is made of keratin, a type of protein found in our bodies.
2. Structure
Now that we’ve got that down pat, we can go deeper into the details. First: Your hair starts in your scalp, no news there. The strand is held in place by the bulb inside of the follicle (the ball-shaped ‘tag’ you can sometimes see on the end of a strand). Each individual shaft comes out of a follicle. Next, the shaft itself has three parts: the cuticle, cortex and medulla. The cuticle is the outside of the hair. It works as the armor that protects the inner core of the strand. The middle section of the strand is the cortex. This section holds the pigment that gives your mane its natural color, and is also the part that physically curves to give your locks their natural texture. The innermost core is the medulla, although not everyone’s strands have this. People with thick locks tend to have medulla and those with thin hair may not.
3. Growth
Growth starts from the papilla in the root bulb. According to Gorkom, “Growth starts from the bottom up, pushing up the hair through the follicle.” There are blood vessels that surround the root and feed it to create more cells. The cells then divide to add to the strand, which in turn causes it to grow.
4. Keratin Loss
Your outer cuticle deteriorates when your locks get severely damaged. This can be due to using heat, chemical treatments and even mechanical processes (brush/combing etc.). The interlocking layers that shield the inner core of the strand open and tear, causing the cortex to lose protein.”This makes it weaker on the inside,” Gorkom states, “but the loss of cuticles (also protein) leaves the hair rough and dull.” To protect your hair from damage, be sure to use a heat protectant, like TRESemmé Thermal Creations Heat Tamer Spray, before blow-drying or heat-styling. You can further strengthen your strands by washing with a keratin infused wash duo, like Suave Professionals Keratin Infusion Smoothing Shampoo and Conditioner.