The first youth activator serum created to compensate the loss of quality due to greying process. For who? - Men & Women, even coloured hair - Greying hair - Thinning hair A true youth serum, Kérastase Densifique Sérum Jeunesse preserves the hair\'s capacity for youthfulness and protects the scalp from the oxidative stress that causes melanin loss. The fiber regains its initial youthfulness and glows with supple softness and dazzling volume. In just three months, a new type of density comes to the fore.