The science
The five-human-type-ceramide complex is the formula's clinically most interesting chemistry. Ceramides AG, AP, EOP, NG, and NP represent the dominant ceramide species in the natural stratum corneum lipid matrix — together with cholesterol and free fatty acids, they comprise approximately 50% of the stratum corneum's intercellular lipids. The published clinical literature on topical ceramide deposition documents barrier-strengthening effects, with the strongest evidence supporting multi-ceramide combinations that mimic the natural matrix composition rather than single-ceramide formulations.
The specific ceramide species differ in their molecular structure and barrier function role. Ceramide NP (also called Ceramide 3) is the most commercially common in skincare; ceramide AP (Ceramide 6) carries an alpha-hydroxy fatty acid component; ceramide EOP (Ceramide 1) contains a long-chain omega-hydroxy fatty acid; ceramide AG and NG are additional species with documented stratum corneum functions. Together, these five forms cover the major ceramide chemistry the skin's barrier depends on.
The five-amino-acid NMF complex (L-serine, L-threonine, L-proline, L-alanine, L-lysine) mimics the natural moisturizing factor that occurs in healthy stratum corneum. NMF is composed of free amino acids, lactate, urea, and other small-molecule humectants generated by the breakdown of filaggrin during the keratinization process. The published research treats topical NMF-mimetic formulations as credible humectant strategies for skin with reduced endogenous NMF (which includes atopic dermatitis, severe dryness, and certain ichthyosis types). The combined ceramide-plus-NMF approach is biologically sophisticated and aligned with current dermatology understanding of stratum corneum function.
Glucosylceramide is a ceramide precursor that the skin can convert to active ceramides through endogenous enzyme activity. The published research supports its inclusion as supporting chemistry for sustained ceramide delivery, particularly when combined with direct ceramide application (as in this formula).
POs-Ca (phosphoryl oligosaccharide calcium) is a starch- and milk-casein-derived ingredient with documented humectant and skin-conditioning effects in Japanese cosmetic research. ETVOS uses it across the Moisture Line as a brand-signature humectant; the published efficacy data supports its contribution to skin hydration and barrier integrity.
The multi-hyaluronic-acid stack (sodium hyaluronate + hydrolyzed hyaluronic acid + sodium acetylated hyaluronate) provides comprehensive surface and deeper-penetrating humectant action through three molecular-weight forms. The combined humectant load offsets the typical post-toner dryness sensitive skin can experience with simpler hydrating toners.
The lavender flower water (Lavandula angustifolia hydrosol) is the byproduct of lavender essential oil distillation and contains a much smaller concentration of the volatile aromatic compounds that drive contact sensitization than lavender essential oil. The published research treats lavender hydrosol as generally well-tolerated even for sensitive skin, though documented lavender or linalool contact allergy remains a contraindication.
The polyquaternium-51 inclusion is a phosphorylcholine-based cationic polymer that contributes barrier-mimetic film deposition during the rinse, supporting the formula's broader barrier-strengthening positioning.