Kérastase Chronologiste Overnight Youth Hair Serum is an intensive overnight treatment designed to support ageing hair by restoring moisture, strength and overall hair quality while you sleep. Formulated with Pro-Xylane™, known for its strengthening properties, it helps reinforce the hair fibre and improve resilience, while Ochrophyta Algae works to deeply hydrate and replenish dry, dull lengths.

As the serum absorbs into the hair overnight, it helps smooth the cuticle, reduce frizz and improve softness without leaving residue or weighing the hair down. The result is hair that feels more supple, looks shinier and is easier to manage, with improved body, bounce and movement over time.

This treatment is scented with the signature Chronologiste fragrance of bergamot, rose and musk for a subtle, luxurious scent that lingers in the hair throughout the day.

Hair benefits after just one night:

• Up to 66% less frizz*
• Up to 32% more shine*
• Up to 92% less breakage*
• 77% say their hair feels revitalised**

The experience is elevated by the signature Chronologiste fragrance of bergamot, rose and musk.

*Instrumental test after 1 use of Overnight Youth Serum
**Consumer test after one application of full Chronologiste routine, bain+masque+Overnight Youth Serum
Test Results Source: Kérastase