Barrier Defense Serum

These describe what an ingredient is, not whether it is a problem. The stance marks above are the ratings; these are not.

• fragrance materialbenzyl alcohol

  • benzyl alcohol: Used both as a fragrance component and as a preservative; the EU names it either way. EU Regulation (EC) 1223/2009, Annex III entry 45: a fragrance substance whose presence must be indicated in the list of ingredients above 0,001% in leave-on and 0,01% in rinse-off products, because of established contact-allergy risk. That entry carries transition footnote (38), which is footnote (37) plus a condition: stock that does not comply may still be made available until 31 July 2028 only "provided that they comply with the restrictions applicable on 15 August 2023", and only if it was lawfully placed on the Union market before the 31 July 2026 cut-off. Entry 45 covers its non-preservative use; it is separately an allowed preservative at Annex V entry 34.

• exfoliating acidlactic acid

  • lactic acid: An alpha hydroxy acid that loosens surface skin cells; it also makes skin more sun-sensitive while you use it. FDA, "Guidance for Industry: Labeling for Topically Applied Cosmetic Products Containing Alpha Hydroxy Acids as Ingredients" (announced at 70 FR 1721, 10 January 2005; FDA web pages title it "Labeling for Cosmetics Containing Alpha Hydroxy Acids"), which names this acid and recommends the statement "Sunburn Alert: This product contains an alpha hydroxy acid (AHA) that may increase your skin's sensitivity to the sun and particularly the possibility of sunburn."

• humectantsodium hyaluronate

  • sodium hyaluronate: A humectant that holds a large amount of water at the skin surface. Chylińska N, Maciejczyk M, "Hyaluronic Acid and Skin: Its Role in Aging and Wound-Healing Processes", Gels 2025;11(4):281, DOI 10.3390/gels11040281, PMID 40277717, open access: hyaluronic acid's "high osmotic activity and anionic structure enable it to bind large amounts of water", and "sodium and potassium hyaluronate are widely used in moisturizing products". The same review notes that high-molecular-weight hyaluronic acid does not penetrate the deeper layers.

• barrier lipidCERAMIDE NP, cholesterol

  • CERAMIDE NP: One of the lipid families the skin barrier is actually built from. Feingold KR and Elias PM, "The role of ceramides in the disruption of the cutaneous permeability barrier, a common manifestation of skin disorders", J Lipid Res 2024;65(8):100593, DOI 10.1016/j.jlr.2024.100593, open access: the barrier lipid matrix "by weight is approximately 50% ceramides, 25% cholesterol, and 15% free fatty acids".
  • cholesterol: One of the three lipid classes that make up the skin barrier, alongside ceramides and fatty acids. Feingold KR and Elias PM, J Lipid Res 2024, open access: the barrier lipid matrix "by weight is approximately 50% ceramides, 25% cholesterol, and 15% free fatty acids". Corroborated by Wertz PW, "Roles of Lipids in the Permeability Barriers of Skin and Oral Mucosa", Int J Mol Sci 2021;22(10):5229, DOI 10.3390/ijms22105229, PMID 34063352.