Keratin Alpha Sleek

Keratin Alpha is the core structural protein inside the hair fiber. It acts as the internal framework that gives each strand its strength, flexibility, and natural shape.

Yes, even persistently frizzy hair responds to the right routine. With Keratin-Alpha Shaper + Amino-Acid Chains, the L’Oréal Professionnel’s Keratin Alpha Sleek Smooth Transformer can reprogram hair for up to 2 weeks of frizz control* after 4 weekly applications. Co-developed with professionals, this loreal keratin alpha sleek routine helps you manage frizz at a structural level for the ultimate at-home smoothing experience.

*Consumer test after 4 applications on 67 consumers.

Build a consistent, weekly routine rather than a one-time fix. Add a smoothening shampoo, a weekly mask, a progressive treatment, and a heat-activated serum to your regular hair care so results carry over between washes.

The L’Oréal Professionnel’s Keratin Alpha Sleek Shampoo is the best starting point, working at the keratin alpha level with every wash. Follow it with the L’Oréal Professionnel’s Keratin Alpha Sleek Smooth Transformer and L’Oréal Professionnel’s Keratin Alpha Sleek Mask for deeper, longer-lasting frizz control.

Frizz is often caused by humidity, hair porosity, heat styling, and a hair fiber that has lost its structural discipline. Powered by Keratin-Alpha Shaper + Amino-Acid Chains, this L’Oréal Professionnel’s Keratin Alpha Sleek range reshapes hair from within rather than just coating the surface, leaving it smoother and more resistant to humidity.

Longer hair tends to lose smoothness at the mid-lengths and ends first, where movement and shine fade fastest. L’Oréal Professionnel’s Keratin Alpha Sleek Smooth Transformer targets this by reshaping the fiber for up to 5x smoother hair*, while the L’Oréal Professionnel’s Keratin Alpha Sleek Serum adds a lightweight, shine-locking finish to the ends.

*Instrumental tests.

For a quick fix, apply the Keratin Alpha Sleek Serum to damp or dry hair, then blow-dry and flat-iron to activate it. For longer-lasting control, build up to it with regular Shampoo, Mask, and Smooth Transformer use beforehand.

A complete routine works best: Keratin Alpha Sleek Shampoo for everyday cleansing, Keratin Alpha Sleek Mask or Keratin Alpha Sleek Smooth Transformer once a week for deep smoothing, and Keratin Alpha Sleek Serum to finish and protect against humidity.

Dry hair often feels rough and lacks shine, while frizzy hair also puffs up in humidity, loses shape quickly, and tangles more easily. A smoothing routine addresses both by conditioning the fiber and improving discipline.

Use the L’Oréal Professionnel’s Keratin Alpha Sleek Mask once or twice a week as part of your routine. Pairing it with the Keratin Alpha Sleek Shampoo helps maintain smoothness, softness, and manageability between Smooth Transformer applications.

Frequent heat styling without protection can weaken the hair fiber and increase frizz over time. The Keratin Alpha Sleek Serum offers heat protection up to 230°C*, helping shield hair from styling damage while locking in smoothness.

*Instrumental tests.

A complete routine typically includes a smoothening shampoo, a weekly mask or progressive treatment, and a finishing serum. Using products formulated specifically for frizz helps improve manageability and reduce the appearance of puffiness.

A professional shampoo does more than cleanse, it helps prep the fiber for the treatments that follow. For full frizz control, pair the Keratin Alpha Sleek Shampoo with the Keratin Alpha Sleek Mask, Keratin Alpha Sleek Smooth Transformer, and Keratin Alpha Sleek Serum.

Look for technologies that reshape the hair fiber from within rather than coating it, such as amino acids and taurine-based actives. This range uses Keratin-Alpha Shaper + Amino-Acid Chains to strengthen and smooth hair while preserving fiber integrity.

Yes. Alongside frizz control, the Keratin Alpha Sleek Mask and Keratin Alpha Sleek Smooth Transformer help reduce unwanted volume, giving hair a sleeker, more disciplined shape without weighing it down.