How long does a keratin treatment last?
Two to four months, and what decides where you land in that range is not the brand of product but how you wash it. It fades gradually rather than stopping: the hair returns to its own texture little by little, so there is no day when it simply ends.
Keratin does not change hair permanently. It fills the fibre and seals it with heat, and that seal loosens with every wash. Hence the single rule that extends the result most: sulphate-free shampoo. Sulphate is the detergent that makes the foam, and it is exactly what strips the treatment out.
The second biggest factor is the starting point. Very curly or very porous hair absorbs well but also releases sooner, and there the result tends towards two months. Wavy, healthy hair gets closer to four.
The first few days matter more than people expect: avoid tying it up or marking it with clips or bands, because the fold sets. Washing with warm rather than hot water helps too.
Worth knowing beforehand: keratin is not a permanent straightening. It does not break the hair's bonds to rebuild them straight, it smooths temporarily. That is why it can be repeated without leaving the hair in two different textures, which is exactly the problem with permanent straightening.
Where this comes from
- Hair smoothing products that release formaldehyde when heated — U.S. Food and Drug Administration
- Brazilian hair straightening — Wikipedia
Also in the glossary
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Every head of hair starts from a different place. The best way is to tell us and have a look.
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