One of the newest crazes in the beauty industry are keratin straightening or smoothing treatments. These processes take kinky, curly or frizzy hair and make it smooth and soft or straight depending on the treatment used. Women all over the world have tried this out and found that even the most hard-to-tame hair can be made soft, silky and manageable.
Wow, can keratin really do that?
Smooth and silky? Sure! But straight? Definitely not.
Remember, keratin is a natural protein that makes up most of your hair. The properties of keratin are amazing in that they can refresh dryness and damage, but if your hair is naturally curly, there is nothing keratin proteins could do to change that.
So what’s the deal with ‘keratin straightening’? To answer this, we need to get into the structural difference between straight and curly hair and exactly how chemical straightening works.
First, what causes curly hair?
To put it simply: genetics. Your genes will determine how straight or curly your hair is. More specifically, your genetics determine the number of disulfide bonds you have within your hair proteins.
See, every hair strand grows from a sac in the scalp called a follicle. In the follicle, keratin and other proteins are created. These eventually die and become the hair shaft (hair is made of dead protein cells being pushed out of the follicle by new, living cells).
The proteins in your hair contain sulphur atoms, which are called sulfides. When two sulfides bond (called a disulfide bond) they can create a bend in the hair fiber. Curly hair has a large number of bonded sulfides, while straight hair has very few.
How does chemical straightening work?
Chemical hair straightening works by breaking down those disulfide bonds in curly hair and resetting them so the hair is straight. This is done in three stages: relaxing, neutralizing and conditioning.
Depending on the treatment, the relaxing, neutralizing and conditioning agents may all be combined into one cocktail, and the hair may be set with a blow dryer or straightening iron, but these are the chemical components:
First the bonds need to be broken down. This is called ‘relaxing’ and is done with chemicals that contain alkalis (do you remember high school chemistry? Alkalis are basic so they denature proteins, meaning they change the way proteins fold over onto themselves).
These alkalis are designed to do a controlled amount of damage: just enough to break down the curls but not so much as to break the hair. The chemical is washed off when the desired amount of damage is done.
The second step is to restore the pH balance of the hair. Since alkalis are basic, an acidic neutralizer will be put on to stop the chemical process and keep your hair from further breakage. At this point, the hair will be straight, but very delicate.
The final step is to apply a conditioner that will repair the hair damage and protect your hair from any additional damage.
So why is it called a ‘keratin straightening treatment’?
You might have guessed by now that the role keratin plays in this whole thing is the conditioning stage of straightening. New developments in keratin hair products mean that damage can be repaired more completely than it has been in the past. Not that it’s a great idea to abuse your hair, but keratin does allow it to recover from some pretty harsh treatments.
What this translates to in the world of hair straightening is the opportunity to use stronger chemicals to break down the sulfide bonds. Formaldehyde, for instance, is occasionally used as an ingredient in the relaxer. The aggressive chemicals allow hair to be straighter for longer and the use of keratin can counteract any damage (though there have been reports of salons overdoing it with the relaxer and serious hair damage as a result—only get this treatment done at a reputable salon).
So while keratin is a major component of a ‘keratin straightening treatment’, it shouldn’t be confused for a straightening agent. The role keratin plays in a keratin straightening system is a positive one by conditioning and strengthening and reversing damaged hair.
As for why the term ‘keratin straightening’ gained popularity, I can only guess that it was for marketing purposes… ‘formaldehyde straightening treatment’ doesn’t have quite the same appeal.