# Hyaluronic Acid

INCI: Sodium Hyaluronate
Category: Active
Concentration: 2.5% (targeted Hyaluronic Spectrum)

> Three molecular weights of Hyaluronic Acid that hydrate at every skin depth, from surface moisture to deep plumping.

## What it does

The sodium salt of Hyaluronic Acid, used in three precisely selected molecular weights as our targeted Hyaluronic Spectrum. High molecular weight protects the surface. Medium molecular weight hydrates the middle layers. Low molecular weight penetrates deep for lasting plump and firmness.

## Why we chose it

We tested 14 different molecular weight combinations over five years of development. Three delivered consistently superior results, blended in a precise ratio, mixed in a specific order, at a controlled temperature. This is the Tri-Active Oligo-Hyaluron Complex. It cannot be replicated by layering two different serums from two different brands. The molecules need to be formulated together to work together.

## Key benefits

Holds up to 1,000 times its weight in water for intense hydration. Three molecular weights work simultaneously at different skin depths. High MW forms a protective moisture film on the surface and prevents water loss. Medium MW builds a sustained moisture reservoir in the upper skin layers. Low MW penetrates deeper, stimulating keratinocyte renewal for structural improvement over time. Smooths fine lines and improves skin elasticity. Calms and soothes sensitive or irritated skin.

## Science notes

2.5% total concentration: the optimal absorption threshold determined through years of real-world testing. Higher concentrations create a sticky surface residue without additional benefit. The sodium salt form has better oxidative stability and lower molecular weight than pure Hyaluronic Acid, enabling superior skin penetration. Peer-reviewed studies using Raman spectroscopy (Essendoubi et al., 2016) have mapped precisely how hyaluronic acid of different molecular weights penetrates human skin. A clinical trial of 76 subjects (Pavicic et al., 2011) found that 50 kDa HA produced significant wrinkle depth reduction after 60 days with excellent tolerability.

## Found in

- COLLAGEN INFUSION - https://www.firstbeautylab.com/en/products/collagen-infusion
- HYALURON PURE - https://www.firstbeautylab.com/en/products/hyaluron-pure
- Hydrate & Glow Duo - https://www.firstbeautylab.com/en/products/hydrate-glow-duo
- Lift & Smooth Duo - https://www.firstbeautylab.com/en/products/lift-smooth-duo
- Renew & Repair Duo - https://www.firstbeautylab.com/en/products/renew-repair-duo
- SILK NIACINAMIDE - https://www.firstbeautylab.com/en/products/silk-niacinamide

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Source: https://www.firstbeautylab.com/en/ingredients/hyaluronic-acid