The myth of Dirty hair + Hair Color

We’ve all heard it before: “Dirty hair is best for color day.” But I’m here to tell you, that couldn’t be farther from the truth.

Was it ever true? Sure. Back in the ’80s and ’90s, The chemicals color lines were a lot harsher than they are today and more likely to irritate the scalp. Not washing your hair for a couple of days before your color appointment would help to create a natural oil barrier for protection. But color has changed. Modern professional color lines have been reformulated to be more gentle, free from ammonia, PPD, and resorcinol. The science behind color has evolved, and so should the advice.

Let’s break it down

Your hair structure is made up of 3 layers

    •    Cuticle : The outermost layer, like tiny roof shingles. A smooth, flat cuticle = shiny, protected hair.

    •    Cortex : The thickest layer. This is where your natural pigment (melanin) lives, and where permanent hair color works its magic.

    •    Medulla : The innermost core. Not always present in fine hair, and still a bit of a mystery.

How Hair Color Works

There are two main types of professional color I want to touch on:

    •    Demi-permanent : color that deposits pigment just under the cuticle layer.

    •    Permanent color : lives in the cortex, meaning the color molecules must make it all the way into the middle of the hair strand.

To get there, two chemical agents are required:

    1.    Alkalizing agent (traditionally ammonia, in organic color MEA): this chemical Swells the cuticle open to allow access into the cortex. The alkalizing agent does most of its work in the first 10- 15 minutes of your color service.

    2.    Oxidizing agent (developer aka hydrogen peroxide): Lightens the natural pigment and activates the new color molecules.

So why does dirty hair mess this up?

When your hair is too dirty or oily, that buildup acts like a barrier around the strands of your hair. The alkalizing agent which uses its power in the first 15 mins of application has to fight through the oil barrier / grime before it can even swell the cuticle layer open. That means it may use up most of its energy just trying to break through oil instead of focusing on what it’s supposed to do: open the cuticle.

If the cuticle doesn’t open properly, the oxidizing agent and color molecules won’t make it into the cortex where they belong. That leads to:

    •    Uneven color

    •    Less vibrant results

    •    Poor grey coverage

• Color that wont last as long

Moral of the story?

Show up with clean, dry hair.

Not freshly clarified or scrubbed raw but a gentle wash the night before your color appointment is ideal. Clean hair = optimal color results.

And if you’re unsure what “clean enough” means, just ask your stylist. We got you.