Since the hairdressers used harsh bleach products with high hydrogen peroxide content in their work, the layer of grease on the strands helped, at least a little, but still reduced the level of damage. Now most stylists work with low oxide formulations – and additional care ingredients to improve hair quality. So, washing your hair before visiting a colorist is not only possible, but also necessary: to save time on the procedure and achieve the best effect from coloring.
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