Hair Health

Discover the Anatomy of Hair

In this Article

While most of us can objectively describe hair — think feeling dry, looking shiny, or a golden blonde appearing brassy — there’s more to hair than meets the eye. Everything from the keratin protein chains that compile a strand itself to the outermost protective F-layer can have an impact on how your hair looks and feels. And that comes down to the anatomy of hair.  

Clearly, there’s a lot that goes into having (and maintaining) healthy hair. Read on as we break down the various layers of hair and how each contributes to your unique hair texture — so you can keep it healthy and strong in the long run. 

At the core of it all: Keratin chains (aka protein chains).  

Let’s start small. At its core, hair is made up of keratin chains, which are the protein building blocks of hair. The interactions between these chains — which are held together by a variety of hair bonds — determine hair’s strength, structure, and overall shape.

The cortex: The crux of the hair follicles.

The cortex is the middle layer of the hair fiber, which contributes to hair’s overall strength and encompasses a whopping 90% of each hair fiber’s weight. When it’s damaged, it can lead to brittleness and weakness, often resulting in breakage if you don’t address it. 

The cuticle: The hair fiber’s enforcer.  

The cuticle is the outer layer of the hair shaft; it surrounds the cortex and protects it from both lifestyle damage and the elements. The cuticle and cortex are both held together by cell membrane complexes; similar to the lipid barrier in skin, these are primarily made up of fatty acids, which pull double-duty to keep moisture within the hair.

The F-layer: The outer protective layer of hair. 

The F-Layer, which is the outermost protective layer of the hair that’s tightly joined to the cuticle, is made up of lipids and a fatty acid layer, which gives hair a smooth, soft look and feel; it’s composed of natural lipids and oils, making it intensely hydrophobic (meaning water can’t easily pass in or, more importantly, out).

Research has found, however, that this all-important F-layer is broken via damage from chemical or color treatments, heat, and other everyday aggressors. That ultimately leaves hair dull, dry, or both — not to mention more vulnerable to additional damage.

Repair the F-layer with Perfect hair Day™ Healthy Hair Perfector 

Since avoiding all damage isn’t a realistic option for many, we’ve created our Healthy Hair Perfector as a way to restore the F-Layer — instantly. Not only does it contain a cuticle-sealing agent, but it also features a bio-based replenishing agent, which targets and restores the F-Layer while actively smoothing the cuticle as well. In doing this, it not only leaves hair softer, shinier, smoother, and healthier looking after one use but also protects the many components of hair within the shaft.

Cuticle-to-cortex repair: Triple Bond Complex 

To undo any damage from the inside out, our Triple Bond Complex works from within the hair. This bond builder for hair features patent-pending 3D Fortifying Technology, which creates a three-dimensional network within the hair to rebuild strands from the inner cortex to the outer cuticle through the creation of hydrogen, ionic and covalent bonds. That leaves hair 8x stronger* and more resistant to future damage while adding softness, smoothness, shine, and manageability after just one use. It’s proof of the power of a comprehensive strengthening treatment that actually repairs hair — with long-lasting results that don’t wash down the drain. 

Together, the two work to strengthen, soften, and smooth hair from the inside out, making it the perfect pairing in any routine. Use Triple Bond Complex once a week as your treatment, and Healthy Hair Perfector as a quick, instant refresh for your healthiest hair yet. 

*Against grooming breakage vs untreated

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Living Proof Review Team

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