Kiehl's Ultra Pure High-Potency 5.0% Niacinamide Serum Versus First Aid Beauty Dark Spot Serum With Niacinamide

Kiehl's Ultra Pure High-Potency 5.0% Niacinamide Serum Versus First Aid Beauty Dark Spot Serum With Niacinamide Detailed comparison of Kiehl's Ultra Pure High-Potency 5.0% Niacinamide Serum versus First Aid Beauty Dark Spot Serum With Niacinamide. This oil-control serum is formulated around Niacinamide to balance excess oil and refine the look of pores. This brightening serum is formulated around Niacinamide and Glycyrrhiza Glabra Root Extract to fade the look of dark spots and brighten dull-looking skin. Water Niacinamide Glycerin Propanediol Methyl Gluceth-20 Hydroxyacetophenone Sodium Hyaluronate Caprylyl Glycol Carbomer Sodium Hydroxide Water, Niacinamide, Glycerin, Propanediol, Methyl Gluceth-20, Hydroxyacetophenone, Sodium Hyaluronate, Caprylyl Glycol, Carbomer, Sodium Hydroxide Dimethicone Aluminum Starch Octenylsuccinate Butylene Glycol Panthenol Polysorbate 20 Actinidia Chinensis Fruit Extract Chrysanthemum Parthenium Extract Glycyrrhiza Glabra Root Extract Camellia Sinensis Leaf Extract Allantoin Aminomethyl Propanol Undecylenoyl Phenylalanine Acrylates/Vinyl Isodecanoate Crosspolymer Dimethiconol Laureth-4 Glyceryl Acrylate/Acrylic Acid Copolymer Phenoxyethanol Disodium EDTA Pvm/Ma Copolymer Tetrasodium EDTA Water, Niacinamide, Dimethicone, Aluminum Starch Octenylsuccinate, Glycerin, Butylene Glycol, Panthenol, Polysorbate 20, Actinidia Chinensis Fruit Extract, Chrysanthemum Parthenium Extract, Glycyrrhiza Glabra Root Extract, Camellia Sinensis Leaf Extract, Allantoin, Aminomethyl Propanol, Hydroxyacetophenone, Undecylenoyl Phenylalanine, Acrylates/Vinyl Isodecanoate Crosspolymer, Dimethiconol, Laureth-4, Glyceryl Acrylate/Acrylic Acid Copolymer, Phenoxyethanol, Disodium EDTA, Pvm/Ma Copolymer, Tetrasodium EDTA Be the first to review These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum. Topically, glycerin does several things at once: Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3. Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin. This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products. Just know very high concentrations (>40%) can feel tacky in low humidity. Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine. Hydroxyacetophenone is a small phenolic molecule that earns its place in a formulas as an antioxidant and preservative booster. As a phenol, it is able to neutralize free radicals to protect both the product and the skin from oxidative stress. Though it can't kill microbes on its own, it works as a good supporting agent when combined with other preservatives like Phenoxyethanol or 1,2-Hexanediol. This ingredient naturally occurs as piceol in Norwegian spruce needles (~0.4-1.1% dry weight and in cloudberries). Though the cosmetic-grade material is synthesized for purity and consistency. You'll usually see it used at low levels and suppliers recommend up to 1% added to a water phase. Safety testing was done at concentrations like 0.05% in SPF products and 0.5% in a Human Repeated Insult Patch Test. The safety evidence is assuring; this ingredient is safe for cosmetics in current use and also holds safety status as a food flavoring as well. An honest caveat: the "soothing" and "anti-inflammatory" claims come mostly from supplier marketing rather than published clinical trials. The Cosmetic Ingredient Review's own literature search found no useful efficacy studies on this ingredient. So the antioxidant and preservative-boosting roles are the well supported ones while the calming benefit is plausible but thinly evidenced. Overall, this is a well-tolerated, low-irritation multitasker that quietly helps a formula stay fresh and stable. Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging. And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin. You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this. In very rare cases, some individuals may not be able to tolerate niacinamide at all or e