It’s the hero ingredient behind many in-salon smoothing treatments (AKA the Brazilian blowout), but what exactly is keratin, and is it good for your hair? The simple answer is: your hair is keratin - a protein that makes up roughly 90 per cent of its structure. When your strands become damaged by external aggressors (such as heat and chemical coloring), their protective layer is broken down, causing these essential proteins to become damaged and depleted. Wondering how in-shower hair care can counteract this?
Protein hair care versus chemical straightening: what’s the difference?
1. While treatments such as the Brazilian blowout rely on chemicals like formaldehyde to straighten texture and nix frizz, protein hair care - such as Nexxus’ Keraphix range - works by seeking out damage on the outer cuticle and plugging gaps to reduce moisture loss and frizz, as well as preventing future breakage. It contains a unique PROTEINFUSION blend with keratin protein and black rice to visibly heal signs of damage. So, if you want to replenish wavy, curly, or coily hair, the Keraphix Shampoo will do just that, without compromising your curl pattern. You may want to combine it with products from the Curl Define range, which contains sweet almond oil and silk protein rich in glycine and serine amino acids (curly hair contains two-to-six times more of these than straight hair).
2. Most people are unaware how damaging daily rituals can be for their hair. Sun exposure, pollution, heat styling, and even heavy-handed brushing can cause the outer lipid layer to raise and crack, leaving the protein-packed inner cortex vulnerable to attack. Keratin hair care works by replenishing like-for-like - plugging gaps in the cuticle in order to align raised cells and boost their moisture-locking, protein-protecting abilities.
3. Here’s the thing about dehydrated hair: it seeks out moisture from the air around it, which is why on a particularly muggy day, your strands tend to swell and rearrange into a halo of fuzz. If you’re a fan of the look, leave it! But if smooth is your style, keratin hair care is the answer. Damaged hair (especially chemically colored hair) is more porous, meaning the cuticle is raised and unable to repel humidity as well. Keratin hair care works by sealing a raised, cracked cuticle, trapping moisture, and keeping frizz-causing humidity out.
4. Bleaching your hair will damage it, sure, but if you like the look, then it’s all about investing in products that offer damage limitation. The Keraphix Keratin Protein Hair collection was designed specifically with severely damaged hair in mind. The most common symptom of damage is split ends - those pesky frayed strands that can’t be completely reversed without a good trim. But, they do need to be sealed and smoothed to prevent further damage between trips to the salon, and that’s where protein hair care comes in. It’s also worth alternating your regular keratin shampoo with a toning one. Blonde Assure Purple Shampoo contains keratin protein (the hair’s building block) plus a purple pigment to help neutralize unwanted yellow and orange tones that tend to pop up in bleached hair.
Practical guidance: how to use keratin-based shampoos for best results
Regular keratin shampoo use helps replenish damaged hair by filling gaps in the cuticle and improving moisture retention. For curly hair, pairing with Curl Define products can support curl pattern while smoothing. If you frequently color or lighten hair, consider a toning shampoo like Blonde Assure Purple Shampoo to manage brassiness without stripping moisture.
Key takeaways
- Keratin is the primary building block of hair and a major factor in its strength and appearance.
- In-salon smoothing treatments may use strong chemicals, but everyday keratin-oriented care focuses on repairing and protecting the cuticle.
- Protein-infused shampoos seal raised cuticles, reduce moisture loss, and help prevent future damage.
- For damaged or chemically dyed hair, targeted keratin products can support restoration between salon visits.
- Alternating keratin with toning formulas can help maintain color while preserving strength and texture.
To enhance informational value, an infographic illustrating how the hair cuticle responds to keratin treatments and how moisture is retained could be useful here.
✅ Keratin Treatments Explained - Here's Everything You need to Know
In practice, Keraphix-style shampoos focus on like-for-like replenishment, plugging gaps in the cuticle, and aligning raised cells to boost moisture-locking and protein protection, which helps keep frizz at bay in humid conditions.
Considerations for different hair types
For wavy, curly, or coily hair, using a keratin shampoo in combination with Curl Define products can support curl integrity while delivering smoothing benefits. For lighter or bleached hair, a purple toning shampoo with keratin protein can help neutralize brassiness while maintaining structural strength.