Sick of Frizz? L’oréal Professionnel’s New Keratin Range Promises Smoother Hair From Here On Out
Nikki is a writer, former makeup artist, and Communications Specialist at Adore Beauty. She kicked off her writing career at Fashion Journal, penning beauty articles and interviewing musicians she’d still name-drop seven years later. In 2023, she made a very big and bold career leap (writing about fashion instead of beauty). Now, she’s come full circle – but still loves to think outside the box.
In Partnership With L’oréal Professionnel
Using L'Oréal Professionnel Keratin Alpha Sleek produced sleeker blow-outs and noticeably reduced frizz; the range claims up to 5x smoother hair and 2x less frizz after four applications. I summarise each product, list exact prices and report how the shampoo, Progressive Treatment, mask and serum performed on wavy and curly hair.
Top Insights From This Guide
- Expect up to 5x smoother hair and 2x less frizz after 4 applications of Shampoo+Transformer+Serum
- Use the Progressive Treatment ($82.50) for progressive smoothing over two weeks, best paired with a blowout
- Choose the sulfate-free Shampoo ($70.40) for fine, dehydrated hair that needs gentle cleansing
- Seal results with the Serum ($80.30) for instant shine and heat protection to 230°C
Read on for concise product notes, which items suit wavy or curly hair, how to use each step for best results, and quick routine choices if you want instant shine or a deeper weekly treatment. The review focuses on real wearability and practical tips rather than lab copy.
My ears perk up whenever a brand like L’oréal Professionnel drops a range that promises transformative results. Thanks to innovative keratin technology, sleek, glossy hair (that stays that way) is well within reach – and actually, a breeze to achieve.
Warning: may cause compliments.
New to Adore, the three-step Keratin Alpha Sleek system works by smoothing the hair fibre at its core, delivering long-lasting frizz control and shine.
The claims are all there – up to 5x smoother hair* and 2x less frizz* – but I’m not a numbers girl, so I tried the range to see it walk-the-walk.
First thing’s first...
What is keratin?
Keratin is a protein naturally produced by the body that helps form each hair strand, along with the nails and outer layer of the skin.
There are two types of keratin in your body (Type I and Type II), and the ones found in your hair are considered alpha-keratins because of their specific form. Think of them as the building blocks for strong, healthy strands.
Loréal Professionnel keratin sleek range
Now, let’s talk products.
While it is only a three-step routine, L’oréal Professionnel launched four products to cover all bases:
L'Oreal Professionnel Keratin Alpha Sleek Shampoo, $70.40
This is a creamy, sulfate-free shampoo that gently cleanses while smoothing and reinforcing hair keratin.
It lathers into a rich foam and leaves your hair feeling clean but not overly squeaky – the sweet spot for fine, dehydrated hair.
L'Oreal Professionnel Keratin Alpha Sleek Progressive Treatment, $82.50
Like the name suggests, this smoothing treatment transforms your hair for two weeks’ worth of frizz control and shine.
Even better, it delivers progressive results with every use, helping your hair become smoother, softer and easier to manage over time.
The Smoother Transformer’s keratin formula is heat-activated, so it’s best paired with a blowout. Don’t threaten me with a good time.
L'Oreal Professionnel Keratin Alpha Sleek Mask, $82.50
The Keratin Alpha Sleek range features a deeply-nourishing hair mask in place of a conditioner, which is designed to be used on wash days when you’re not reaching for the Smooth Transformer.
It does its thing (soften, hydrate, smooth) in just 5 minutes, so it’s perfect for when you want smooth results sooner.
L'Oreal Professionnel Keratin Alpha Sleek Serum, $80.30
The final step for long-lasting smoothness involves sealing the hair’s keratin structure, which is a job for the Mirror Sleek Serum. The quick wins? Instant shine and heat protection up to 230°C.
The results:
As expected, using the range for a few weeks has made my blow-outs look sleeker and my strands feel smoother.
What’s even more impressive though, is that my rough, air-dried curls (my look when I don’t have the time or mental energy to diffuse) haven’t been as frizzy.
Though ‘sleek’ seems to be the selling point for this range, I’d recommend it first to anyone with wavy or curly hair. ‘Cause we know frizz. This isn’t an official claim, nor something L’oréal Professionnel even hints at, but I noticed that my hair felt cleaner between washes, too.
Whatever the science, I’m a fan.
*Instrumental test after 4 applications of the routine Shampoo + Smooth Transformer + Serum.
*Instrumental tests with Smooth Transformer.
