Short answer: A gloss is a care treatment that increases how evenly light reflects off the hair surface, aiming at shine and a more uniform look. It differs from permanent colour in that its purpose is not to change the colour but to refine the appearance you already have. The result depends on the hair's current condition and fades over time, so it is best treated as a step repeated within a care schedule.
What a gloss does
A gloss smooths the outer surface of the hair shaft so that light reflects more evenly. In visible terms that means shine, a more vivid impression of colour and less dullness. The effect is most noticeable on hair that is worn, heat-styled or looking flat.
How it differs from colour
Permanent colour changes the hair by acting on its structure. A gloss works largely on the surface and aims to strengthen the existing colour and balance the tone. For that reason it should not be chosen with the expectation of lifting several shades or fully covering grey.
Who it suits
Typical uses are guests who do not want to change colour but want to refine the look, hair that has gone flat through heat and environmental exposure, and hair whose tone needs balancing after colouring. Suitability is assessed beforehand against texture and treatment history.
Longevity and repetition
The effect is not permanent; it diminishes with the number of washes, the products used, heat styling and water hardness. It is therefore more realistic to think of it as a step repeated at intervals within a care plan rather than a one-off treatment.
When to seek professional advice
Where there is heavy breakage, loss of elasticity or a history of repeated chemical treatments, assessment before application becomes important. If the scalp shows itching, redness or sensitivity, it is sensible to consult a healthcare professional before a cosmetic treatment.
When is a professional assessment needed?
If there is an active infection, an open wound, marked sensitivity, a history of allergy, medication use or an unexpected reaction, consult a healthcare professional before any cosmetic treatment. This content is for general information and does not replace medical diagnosis or treatment.
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