Retinol Mixer

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

• exfoliating acidLactic Acid, Glycolic 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."
  • Glycolic 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."

• retinoidRetinol

  • Retinol: A vitamin A derivative that speeds skin turnover; dryness and flaking while skin adjusts are its usual accompaniment. SCCS Opinion on Vitamin A (Retinol, Retinyl Acetate, Retinyl Palmitate), SCCS/1576/16, final version of 6 October 2016; Commission Regulation (EU) 2024/996 added the group to EU Regulation (EC) 1223/2009 Annex III entry 376, capping it at 0,05% retinol equivalent in body lotion and 0,3% in other leave-on and rinse-off products, with the label statement "Contains Vitamin A. Consider your daily intake before use."

• humectantGlycerin, Sodium Hyaluronate

  • Glycerin: A humectant, and one of the two ingredients a comparison of moisturiser components found made a significant difference to skin hydration. FDA OTC skin protectant monograph, 21 CFR 347.10(h), lists glycerin as a skin protectant at 20 to 45%. On the humectant half: Jeong CB, Han JY, Cho JC, Suh KD, Nam GW, "Analysis of electrical property changes of skin by oil-in-water emulsion components", Int J Cosmet Sci 2013;35(4):402-410, DOI 10.1111/ics.12059, PMID 23621673, found that "glycerine and urea showed significant skin hydration effects compared with other humectants".
  • 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.

• soothingNiacinamide

  • Niacinamide: A vitamin B3 form that supports the skin barrier and has anti-inflammatory activity; it turns up in products aimed at acne, rosacea and eczema. Camillo L, Zavattaro E, Savoia P, "Nicotinamide: A Multifaceted Molecule in Skin Health and Beyond", Medicina (Kaunas) 2025;61(2):254, DOI 10.3390/medicina61020254, PMID 40005371, open access: it "is extensively used in ... the treatment of dermatological conditions such as blistering diseases, atopic dermatitis, rosacea, and acne vulgaris", and contributes to reducing inflammation. On the acne evidence specifically: Liu H, Yu H, Xia J, Liu L, Liu GJ, Sang H, Peinemann F, "Topical azelaic acid, salicylic acid, nicotinamide, sulphur, zinc and fruit acid (alpha-hydroxy acid) for acne", Cochrane Database Syst Rev 2020;5:CD011368, DOI 10.1002/14651858.CD011368.pub2, PMID 32356369, records "low-quality evidence" for every nicotinamide comparison it could pool, and none of its four nicotinamide studies measured the physician global assessment at all.