Collagen straightening: a hand on dark, smooth, glossy hair after the treatment

The softness of hair after collagen comes from the hair itself, not from a coating.

Collagen straightening. What collagen does.

Collagen is not a marketing word. It is a protein, and it has a precise role in straightening. Here is what it does, and what it does not.

By the HER BOSS teamUpdated: September 2026Reading time: about 3 minutes

Collagen, without the magic

Collagen is the most common protein in the body. It does not occur naturally in hair, but collagen broken down into small particles (hydrolysis) can bond to the hair's cuticle, fill cracks and hold moisture. That is what gives the feeling of soft, shiny hair, and the smooth sealing of the hair's surface.

What collagen does not do: it does not build the hair's framework and it does not straighten. The framework is keratin. So a "collagen straightening" that relies on collagen alone will give softer, shinier hair, but not straight hair, and not for long.

Why two proteins and not one

Keratin enters the gaps created by colour, heat and sun, and rebuilds the structure that holds the hair straight. Collagen closes the cuticle over it and keeps moisture inside. One builds, the other seals. Without the first there is no straightening; without the second you get smooth hair that feels like straw.

That is why Herboss straightening was developed with both proteins in a single formula, and not as a collagen treatment added after straightening.

What you feel afterwards

  • Softness that lasts even after washing, because it comes from the hair and not from a coating.
  • The shine of a closed cuticle, not of silicone.
  • Less breakage at the ends, because the hair holds moisture.
  • The same colour. Collagen does not lighten or change the shade.

Collagen in a mask versus collagen in straightening

A collagen mask is a moisture treatment: the collagen sits on the hair, softens it and washes out after a few washes. In straightening with collagen, the protein is sealed inside the hair with heat together with the keratin, so the softness does not wash out. Both are good; they are simply not the same thing, and a very different price between them is reasonable.

What happens over time

Treated hair keeps its softness and shine for as long as it exists, because they come from the hair itself. What grows from the root is new, natural hair, and that is treated next time. Washes with salts, very hot water and chlorine shorten the result of any straightening, and this one too.

Collagen, silicone and the difference you can feel

Silicone gives instant shine because it coats the hair with a smooth layer on the outside. After two or three washes it comes off, sometimes leaving hair heavy and dull. Hydrolysed collagen enters the cuticle and holds moisture from within, so its softness feels different: light, not greasy, and lasting. That is why in the Herboss straightening protocol hair is washed at the salon with salt-free shampoo and not finished with a silicone serum.

Who it matters to most

For coloured and bleached hair that has lost moisture and elasticity. For dry, brittle hair. And for hair that has been straightened before and has become stiff. In these cases the difference between one protein and two is the difference between straight hair and healthy hair.

Frequently asked questions

Is collagen straightening the same as a collagen treatment?

No. A collagen treatment is a mask or moisture treatment that washes out after a few washes. Straightening with collagen is a protocol in which the collagen is sealed into the hair with heat together with the keratin.

Does collagen lighten hair?

No. The colour does not change and does not lighten.

Can collagen straightening be done on bleached hair?

Yes, and it is one of the situations where collagen makes the biggest difference. On heavily bleached hair a strand test is done first.

How long does the softness last?

For as long as the treated hair exists. In the Herboss straightening protocol, only the regrown root is treated afterwards.

Is the collagen in hair the same collagen as in supplements?

The same protein family, but supplements work through the body, while hydrolysed collagen in hair works directly on the hair. One does not replace the other.

HER BOSS Gold Line

Keratin and collagen. No formaldehyde. Registered with the Israeli Ministry of Health.1