Hair aging happens at the scalp — not at the ends. The visible signs (loss of density, lack of vitality, thinning, dullness, frizz) originate at the follicle level, where the scalp's cellular environment progressively loses its capacity to support healthy hair growth. Kérastase Chronologiste Longevity Potion is a leave-in scalp concentrate built specifically around that science: a lightweight, fast-absorbing serum that acts 10 layers deep into the scalp to reboost cellular activity and optimize the environment for the 3 billion scalp cells responsible for hair regeneration. The formula centres on 3% Pro-Xylane™ — Kérastase's proprietary green chemistry molecule derived from beech wood xylose — which densifies the scalp matrix by stimulating the extracellular matrix proteins that support follicle anchoring and hair thickness. Ochrophyta Algae (bio-sourced deep-sea kelp extract, Macrocystis Pyrifera) delivers a concentrated profile of marine minerals that protect the scalp against daily environmental aggressors and provide deep cellular revitalization. Used every 3 days for one month, the treatment works progressively to make hair appear thicker, denser, and healthier for longer.
How to use: Shake well. Apply on towel-dried scalp every 3 days for 1 month. Distribute 5 doses section by section (1 dose = 1 pipette filled to the mark). Leave in — do not rinse. In case of eye contact, rinse immediately and thoroughly. Pair with Chronologiste Overnight Youth Serum on lengths and ends as the second step of the nighttime ritual.