Keratin, the foundation of our hair!

Keratin shampoo, keratin mask, keratin treatment... Keratin is a widely used ingredient in hair care, and for good reason! But what exactly is keratin and what does it do for hair? In this blog, you'll find all the technical info about this very popular and essential substance! Next week, we'll discuss ways to add keratin to your hair and how to choose the right products.

Hair Structure

First, let's go back to basics and understand how our hair is built. A hair consists of 3 layers: the cuticle, the cortex, and the medulla. The cortex is the layer that matters when talking about keratin. It naturally contains a balanced amount of moisture and keratin. Depending on the hair type, the percentage of keratin varies from 80 to 95%. For example, Asian hair has a higher percentage of keratin, about 94%, and African hair has 85%. European hair contains 89% keratin and is also composed of 8% moisture and 3% minerals.

What is Keratin?

Keratin is an endogenous building block, a protein, found in our hair, skin, and nails. It is formed by various amino acids, the building blocks of proteins. One of the most important amino acids in keratin is cysteine, which affects the quality of the disulfide bonds in our hair. These disulfide bonds give hair strength and determine its shape: straight, wavy, or curly.

The Right Balance

The ratio of keratin to moisture in your hair is genetically determined. Your body maintains the correct balance, from within. However, this balance in the hair can be disrupted, mainly by external factors:

Chemical treatments (coloring, bleaching, perming)
High temperatures from styling tools
The weather (sun, wind, and rain)
Chlorine and sea salt
Low-quality hair care products
Hair aging

Disrupted Keratin-Moisture Balance

Our skin can repair a disrupted keratin balance itself; keratin is replenished as needed. This is not the case for the keratin content in our hair. Hair that has less keratin than it naturally should will retain more moisture. This makes it heavier and causes it to lose elasticity and volume. Your hair weakens and loses its strength and resilience, becoming frizzy, brittle, and dull.