Hair protein VS keratin: Which one suits your hair?

It’s a question many women ask at salons and online:
“Should I go for keratin or protein treatment?”

Although both treatments promise smoother, shinier, and frizz-free hair, the difference between hair protein and keratin lies in their composition, the way they work, and the type of hair each is best suited for.

In this professional guide, we’ll explain the technical distinctions between protein and keratin treatments, how to choose the right one for your hair, and how Belas Store’s professional collections can help you maintain the best results safely.

What is keratin treatment?

Close-up of a woman receiving a keratin treatment with a hairstylist using a flat iron and blow dryer simultaneously to seal the product.

Keratin is the primary natural protein found in hair, nails, and skin it makes up about 80–90% of the hair’s structure.
Over time, factors like heat styling, UV exposure, chemical dyes, and harsh shampoos strip away this natural keratin, leading to dullness, dryness, and frizz.

How does keratin treatment work?

Keratin treatment works by reinfusing the hair shaft with a synthetic or natural keratin complex that smooths and coats each strand.
When heat is applied, the formula seals the outer cuticle layer, leaving hair visibly straighter, glossier, and more manageable.

Expected results:

Up to 90% reduction in frizz
Smoother, straighter hair
Enhanced shine and silkiness
Protection against humidity

The results typically last between 3 to 6 months, depending on post-care and washing frequency.

What is hair protein treatment?

Protein treatment is a more advanced and restorative version of hair repair therapy.
It focuses on nourishing and rebuilding damaged hair fibers from within using a blend of amino acids, collagen, natural oils, and restructured keratin.

How does it work?

Unlike keratin, which mostly smooths the outer surface, protein treatment penetrates deep into the hair cortex to rebuild its internal structure.
It:

Fills cracks in the hair shaft
Restores elasticity and strength
Improves moisture retention
Reduces breakage and brittleness

This makes protein treatment perfect for weak, damaged, or chemically processed hair that needs deep repair rather than intense straightening.

Scientific difference between keratin and protein

Close-up of a person running fingers through smooth, shiny, straight hair after a professional protein or keratin treatment.

Aspect	Keratin Treatment	Protein Treatment
Composition	Concentrated keratin with surface-coating agents	Mix of amino acids, collagen, and natural oils
Mechanism	Coats the outer cuticle for a sleek finish	Repairs internal fibers and rebuilds structure
Result	Straighter, smoother, and polished hair	Softer, more natural, flexible hair
Longevity	3–6 months	2–4 months
Heat during application	High heat (200–230°C) to seal keratin	Moderate heat for absorption
Suitability for colored hair	May slightly alter hair color tone	Safe for dyed or bleached hair
Best suited for	Very curly, thick, or frizzy hair	Weak, dry, fine, or color-damaged hair

When should you choose keratin treatment?

Keratin treatment is ideal for:

Thick, coarse, or very frizzy hair that needs strong smoothing.
Clients seeking long-lasting straightness and shine.
Those who style their hair frequently with heat tools.

Always ensure the product is formaldehyde-free and uses safe ingredients.
Formulas such as Sleeker Plus Ultra Control Protein are designed to deliver a powerful smoothing effect while protecting the hair’s health.

When should you choose protein treatment?

Protein treatment is perfect for:

Dry, brittle, or color-treated hair that needs nourishment.
Those who want to restore health and manageability without complete straightening.
Hair that has lost elasticity and appears lifeless or weak.

Treatments like Aya Brazil Glossy Perfect Kit and Oil Therapy NCC Kit offer deep restorative care, replenishing the hair’s natural proteins while maintaining a soft, natural look.

How to know if your hair needs protein rather than keratin

Your hair likely needs protein treatment if:

It feels fragile, breaks easily, or lacks strength.
It’s color-treated or over-processed.
It looks dull and dry even after conditioning.
It can’t handle heat or feels limp after styling.

In contrast, if your hair is very thick, curly, or frizzy and hard to manage daily, keratin will give you a smoother, straighter appearance that lasts longer.

Can you combine protein and keratin treatments?

Yes, some modern professional systems such as the Sleeker Plus line combine restructured keratin with plant-based proteins to balance both smoothing and repair.
This hybrid approach achieves sleek, manageable hair without sacrificing flexibility or internal strength.

Aftercare for both treatments

Smiling woman with long, shiny brown hair holding it in her hands, showing smooth and healthy texture after a professional treatment.

No matter which treatment you choose, post-care is essential for maintaining results.
Follow a routine using safe, professional products available at Belas Store:

Product	How to Use	Benefit
Sleeker Magic Spray	Apply after washing or before styling	Provides heat protection and instant shine
Dream Care Serum	Use after drying or before styling	Smooths split ends and adds softness
Color Care Serum	Ideal for colored hair	Preserves color and boosts vibrancy

Avoid shampoos containing sulfates or sodium chloride, as they strip away the protective coating left by the treatment.

Which one is better?

There’s no absolute “better” treatment only what’s right for your hair:

Keratin treatment: Best for thick, curly, or frizzy hair that needs long-lasting straightening
Protein treatment: Best for dry, damaged, or color-treated hair that needs repair and nourishment.

Your choice depends on your hair’s current condition and your styling goals whether you prefer a sleek, straight finish or a naturally soft, healthy look.

Conclusion

The difference between hair protein and keratin lies in their purpose and depth of action.
Keratin primarily smooths and coats the outer layer for immediate shine, while protein works deeper to rebuild and restore the hair’s inner strength.

Choosing the right one ensures not just a beautiful result, but long-term hair health.
Explore professional-grade, formaldehyde-free treatments and post-care solutions at Belas Store, where you’ll find premium formulations tailored to every hair type and need.