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This Is What Happened When I Had A Keratin Treatment

What happened when Stylist beauty editor Morgan Fargo had a keratin hair treatment at Hershesons hair salon in London.


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The author with natural vs. smoothed hair

The list of things Meghan Markle and I have in common is incredibly limited. As it stands right now, the gamut runs from a familiarity with  Suits and  a penchant for pared-back make-up. That was until five months ago when I had a permanent blow-dry hair treatment. Now, the list extends to three. 

A hair procedure loved by celebrities and people who want to do less to their hair, a permanent blow-dry can also be referred to as a keratin treatment or, on occasion, a Brazilian blow-dry (although the latter tends to specify a particular brand of the treatment rather than the treatment itself).

What is a keratin hair treatment?

Famed for its ability to smooth, add shine and condition the hair, a permanent blow dry works to minimise frizz, soften coarseness and increase manageability. As the name suggests, its primary role is to create the effect of a blow-dry that doesn’t wash out. It can last for up to four months – providing you use the correct styling and haircare products.

“Keratin treatments are really kind on the hair and they’re great for condition,” explains Luke Hersheson, CEO of one of London’s most prestigious hair salon brands, Hershesons. “If you’ve got dry or damaged hair, the condition of it will come out better post-treatment as it tends to make it silkier and shinier. Keratin is a protein, so it puts loads of keratin back into the hair.”

“And actually, the more coloured your hair is, the bigger difference you’ll notice because the cuticles are more raised, so it’s easy for it to penetrate inside the hair.”

How does a keratin hair treatment work?

A fairly simple process – incredibly so, when the longevity of the treatment is taken into account – a keratin hair treatment always starts with a clarifying, sulfate-free hair wash. This helps remove product build-up and dirt from the hair ahead of the formula being applied. 

Then, when the hair is combed through and still wet, the formula is applied from roots to ends and brushed onto the hair from a small bowl. The mixture contains the ingredient formaldehyde – a colourless, odourless substance that is commonly used in building materials. However, when used at incredibly low percentages, like 0.1% to 0.2% in a keratin hair treatment, it works to bond the keratin to the hair and is safe for human use. While allergic reactions to a keratin treatment can occur, they are rare. A patch test prior to the treatment is advised. 

Please note: the safety of the procedure is heavily reliant on how much formaldehyde is used in the formula. Thorough research prior to treatment is an absolute necessity. 

Then, after the treatment has been applied, it is blow-dried and then straightened into the hair using a pair of tongs. This sealing process leaves the hair stick straight and slightly lank-feeling. For the next two to three days, the hair should not be tied up or made wet in any way. Warm body showers are the best option as hot baths emit steam that can sabotage the treatment.

How long does a keratin hair treatment last?

After 48 or 72 hours, the treatment can be washed out using a sulfate-free shampoo and conditioner. A treatment that gradually wears off, the initial weeks leave hair almost stick-straight and impossibly shiny. Primarily a smoothing treatment, be prepared to lose a little of the hair’s natural volume – especially if you have usually curly or wavy hair with a lift at the root. Over time (around three to six months) the effect will slowly lessen and hair will return to its natural state.

Please also note: if you have fine hair or like the body of your natural hair, a keratin treatment could knock this out for the period of time it takes the treatment to wear off. 

“If your hair is fine and you don’t feel like you get enough body, then it is going to reduce the body and the volume to some degree. When you have very curly or frizzy hair, you’re never really bothered about the body or the volume because you’re probably always trying to flatten it and make it smoother, so it’s not as much of a concern,” explains Hersheson. “If you have fine hair that is frizzy and you love the volume, you probably want to be more concerned about it reducing volume. Options are having the treatment done but focus it only on the hairline or don’t do the entire thing.”

What happened when I had a permanent blow dry at Hershesons, London

Blessed with unruly hair that has a tendency to puff up on contact with humidity, I felt excited about the prospect of a summer of hair that could go from sea to shower to supper without much doing to it. Previously, I was slathering hair oil nightly and tightly braiding my hair to make it feel a little more manageable. A no-heat way to increase softness and shine, it was time-consuming and meant I had to remember the night before if I wanted smooth hair in the morning. 

Post-treatment and after I had waited the necessary three days (during which it did become incredibly lank-looking), I washed my hair and was met with smooth, soft, very straight hair. Over the next few weeks, I felt as if my hair settled and natural volume crept back in. The feeling of streamlining my getting-ready routine (and entirely nixing heated tools and blow-dries) was unparalleled. In the mornings before work, I could wash and go, making do with a slick of lip gloss, a pat of blush and a small amount of hair oil rubbed into the ends. 


Three months later and a natural wave has emerged, closer to my original hair texture but still a world away from the brittle, frizziness I was facing before. Interestingly, I’ve found the slow re-emergence of my natural curl pattern to be a joyful exercise – each day I look forward to seeing a little more of it poke through. While I’ll probably return for another keratin treatment next spring, ahead of the sun-salt-sea season, I’m looking forward to playing with curly hairstyles again. Temporary and time-saving, it allowed me the space to play at having smoother, straighter hair without causing any excess damage in the process. That’s kind of incredible, no?

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This post originally appeared on Stylist and was published March 5, 2022. This article is republished here with permission.

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