what is hair

What is Hair Made Of? Understanding the Structure of Hair

A mini lesson that's all about the structure of your hair!

What is hair? A lot of us may be curious about the composition of hair and why it looks, feels, and behaves differently from person to person. 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 informed on your crowning glories from the inside out. Read on to learn more about hair’s structure and how it grows.

What Is Hair Made Of?

what is hair made of? natural hair
Learn everything you need to know about hair. Photo credit: Craig Alexander

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 on 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.

what is hair made of? long hair
Keep your hair healthy and happy. Photo credit: Craig Alexander

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 the use of 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 Spraybefore 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.

The more we understand our hair, the better we can care for it!

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