Hair gloss: what is this technique that makes hair shine?

Hair gloss is a semi-permanent coloring technique designed to subtly alter color while imparting radiance to the hair fiber.

Unlike an oxidative hair color , which lifts the cuticle scales and alters the internal pigments, gloss is based on an acidic formulation in which the pigments deposit on the surface, between the cuticle scales, without penetrating the cortex. As a reminder, each hair fiber is organized into three superimposed layers. The outermost layer, the cuticle, is composed of keratinized scales that interlock like shingles and serve a protective function. Beneath this layer lies the cortex, the largest region of the hair, rich in keratin and pigments. The cortex is responsible for the hair’s mechanical strength and its color. Finally, the medulla, or marrow, constitutes the central part but plays little role in the hair’s physical properties.

The absence of oxidation in hair gloss accounts for its gentleness: the hair isn’t sensitized, and the resulting shade gradually fades, like a tan, without leaving any demarcation. The base of hair glosses generally includes cationic agents, which electrostatically bind to the fiber to smooth, detangle, and temporarily strengthen the lengths, along with moisturizing agents that enhance the hair’s optical quality. This technique also differs from a glaze, which uses mildly oxidizing agents that can weaken the hair if applied too frequently. Hair gloss therefore positions itself as an intermediate alternative: pigmented enough to enrich a hue or correct an undesirable one, yet gentle enough for both natural and colored or sensitized hair.

Hair gloss is a very popular treatment among individuals wishing to enhance their hair without damaging it. Thanks to its semi-permeable formula, it allows you to intensify an existing tone, add a subtle nuance, or, conversely, neutralize an undesirable shade, such as yellow, golden, or copper undertones, common after bleaching or a sun exposure prolonged. Hair gloss can also warm or cool a color, darken it slightly by up to two shades, or even create a new tone in the hair. Hair gloss can also be used to conceal early white hairs, blend them into the rest of the hair and soften an overly pronounced balayage to achieve a more natural appearance. Very useful for correcting visible regrowth, gloss is also suitable for colored hair or for those hesitant to take the plunge and get highlights.

Hair gloss has a transient nature that, depending on one’s perspective, can be regarded as either an advantage or a drawback. In fact, its effects persist for 6 to 10 weeks.

A systematic review of 22 studies published between 2010 and 2023, involving about 1,000 volunteers, analyzed 150 hair gloss products and confirmed their benefits. Although the results presented below are subjective and solely reflect participants’ perceptions, they still offer useful insights and demonstrate the overall satisfaction of hair gloss users.

As mentioned above, a hair gloss is a semi‐permanent coloring formulated to deposit pigments on the hair surface. It relies on mild chemistry, characterized by an acidic, ammonia‐free formula. This acidity allows for tightening of the cuticle scales, which improves light reflection and accounts for the highly distinctive shine achieved after the treatment.

More specifically, the pigments present in a gloss bind between the hair cuticles through weak interactions (hydrogen bonds, van der Waals forces), which explains the temporary nature of its hold. Since it does not alter the hair’s internal chemistry, a hair gloss cannot lighten it. It can only darken it slightly or neutralize unwanted tones. Hair glosses also contain a cationic complex, that is, positively charged molecules capable of adhering to keratin, a molecule that is negatively charged. This promotes an immediate conditioning effect.

Did you know? Cationic agents are also found in conditioners and hair masks, which are responsible for the conditioning effect of these hair care treatments.

A hair gloss treatment follows a straightforward yet methodical protocol. It can be carried out in a salon or at home.

When a hair gloss treatment is performed in the salon, it all begins with a diagnosis of the desired shade and an assessment of the hair fiber’s condition (porosity, split ends…). This step is crucial, as not all gloss treatments address the same needs, particularly in terms of neutralizing or intensifying highlights. It’s also at this point that the colorist chooses between a single gloss (one shade) or a double gloss (two shades), used when one wants to blend the roots, correct an overly contrasting balayage, or naturally conceal gray hair.

The gloss is then applied to slightly damp hair. The semi-permanent formula is evenly distributed throughout the hair or only on specific areas. The stylist ensures uniform saturation of the lengths. The processing time generally ranges between 10 and 30 minutes, depending on the shade, porosity, and targeted result. The gloss is then rinsed thoroughly, followed by an acidic or conditioning treatment designed to stabilize the shine and extend the longevity of the outcome. Then it’s time to dry the hair, instantly revealing the radiance achieved with the hair gloss.

Note : Hair stylists generally recommend a hair gloss treatment every three months, but it can be applied every five to six weeks to maintain the results.

It is also possible to perform a hair gloss treatment at home, but results are often less satisfactory. In addition to the products used—which are generally of higher quality in salons—professional stylists have greater control over the technique: selecting the gloss color based on the hair’s undertone, measuring the neutralizing agent dosage, adjusting processing time to the fiber’s condition, and applying it evenly strand by strand. At home, even with a high-quality product, these parameters are harder to regulate, which explains occasionally uneven outcomes, variable shine, and shorter-lasting effect.

Although it imparts shine and highlights, hair gloss has certain limitations you should be aware of before getting started. Its effects are short-lived: the gloss typically fades after six to ten weeks, depending on hair fiber porosity, wash frequency, and the products used. Additionally, if you’re looking to use hair gloss to mask gray hair, don’t expect full coverage : this technique simply softens the contrast and helps blend the grays into your base color.

As a precaution, we recommend performing a skin patch test, because even though hair gloss contains fewer oxidizing agents than a traditional hair dye, it can still cause reactions in sensitive individuals, including irritation or allergic reactions. You should also avoid applying a hair gloss that is too dark on highlighted or lightened hair, as it may produce a dull or slightly greenish cast. Finally, for those who want to do a hair gloss treatment at home, it is important to strictly follow the usage instructions, because an excessively long application time or uneven distribution can lead to irregular results. In a salon, the stylist adjusts both the formula and the application technique, which minimizes these risks.

• BONTOZOGLOU C. & al. In vivo human hair hydration measurements by using opto-thermal radiometry. International Journal of Thermophysics (2018).

• RIBEIRO A. & al. Biotechnology of functional proteins and peptides for hair cosmetic formulations. Trends in Biotechnology (2022).

• MEHRA S. BH12 Efficacy and safety of hair gloss treatments: A systematic review of licensed products in the UK. British Journal of Dermatology (2025).