Practice 'double shampooing' by using clarifying or detoxifying products to bind and thoroughly remove impurities accumulated on the scalp and hair fiber.

noli's read

In terms of cosmetic formulation, the principle of surfactants binding to fatty substances (sebum, pollution) to rinse them away with water is scientifically validated. The first wash removes this surface layer, while the second cleans the scalp more deeply, as confirmed by analyses from the hair research institute TRI Princeton. This is also why the second wash generally lathers much more, as the surfactants are no longer saturated by surface oil. However, the systematic use of so-called 'clarifying' or detoxifying shampoos for this double wash is considered excessive. Experts like dermatologist Dr. Joel Schlessinger point out that these powerful formulas, if used too often, risk stripping away the natural protective lipids of the hair fiber. This can lead to dryness or scalp sensitivity. For a balanced routine, research suggests reserving this method for occasional needs (buildup of styling products) and using gentle formulas for daily use.

the sources

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