Paula's Choice C5 Super Boost Moisturizer Versus Kiehl's Ultra Facial Moisturizer

Paula's Choice C5 Super Boost Moisturizer Versus Kiehl's Ultra Facial Moisturizer Detailed comparison of Paula's Choice C5 Super Boost Moisturizer US versus Kiehl's Ultra Facial Moisturizer. This brightening moisturizer is formulated around 3-O-Ethyl Ascorbic Acid and Ascorbyl Glucoside to brighten dull-looking skin. This day moisturizer is formulated around Squalene to hydrate skin. Water Dicaprylyl Carbonate 3-O-Ethyl Ascorbic Acid Dimethicone Butylene Glycol Polyglyceryl-6 Distearate Ascorbyl Glucoside Squalane Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer Acetyl Sh-Hexapeptide-5 Amide Acetate Citrullus Lanatus Seed Oil Hydrogenated Lecithin Theobroma Cacao Seed Butter Hydrogenated Phosphatidylcholine Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate Sodium Hyaluronate Oryza Sativa Bran Extract Propanediol Jojoba Esters Tocopherol Acetyl Zingerone Cetyl Palmitate Caprylyl Glycol Cetyl Alcohol Polyglyceryl-3 Beeswax Sodium Hydroxide Sorbitan Olivate Sorbitan Palmitate Helianthus Annuus Extract Ethylhexylglycerin Hexylene Glycol Sodium Phytate Polysorbate 60 Sorbitan Isostearate Lecithin Rosmarinus Officinalis Leaf Extract Glycine Soja Oil Lysolecithin Bacillus Ferment Citric Acid Polyglutamic Acid Beta-Sitosterol Phytic Acid Squalene Phenoxyethanol Sodium Benzoate Potassium Sorbate Water, Dicaprylyl Carbonate, 3-O-Ethyl Ascorbic Acid, Dimethicone, Butylene Glycol, Polyglyceryl-6 Distearate, Ascorbyl Glucoside, Squalane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Acetyl Sh-Hexapeptide-5 Amide Acetate, Citrullus Lanatus Seed Oil, Hydrogenated Lecithin, Theobroma Cacao Seed Butter, Hydrogenated Phosphatidylcholine, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Hyaluronate, Oryza Sativa Bran Extract, Propanediol, Jojoba Esters, Tocopherol, Acetyl Zingerone, Cetyl Palmitate, Caprylyl Glycol, Cetyl Alcohol, Polyglyceryl-3 Beeswax, Sodium Hydroxide, Sorbitan Olivate, Sorbitan Palmitate, Helianthus Annuus Extract, Ethylhexylglycerin, Hexylene Glycol, Sodium Phytate, Polysorbate 60, Sorbitan Isostearate, Lecithin, Rosmarinus Officinalis Leaf Extract, Glycine Soja Oil, Lysolecithin, Bacillus Ferment, Citric Acid, Polyglutamic Acid, Beta-Sitosterol, Phytic Acid, Squalene, Phenoxyethanol, Sodium Benzoate, Potassium Sorbate Propylene Glycol Dicaprylyl Ether Glycerin PEG-100 Stearate Glyceryl Stearate Hydrogenated Polyisobutene Sorbitan Oleate Acrylates/C10-30 Alkyl Acrylate Crosspolymer Triethanolamine Beeswax Disodium EDTA Stearic Acid Myristyl Alcohol Prunus Amygdalus Dulcis Oil Prunus Armeniaca Kernel Oil Persea Gratissima Oil Water, Propylene Glycol, Dicaprylyl Ether, Glycerin, PEG-100 Stearate, Glyceryl Stearate, Squalene, Hydrogenated Polyisobutene, Phenoxyethanol, Sorbitan Oleate, Caprylyl Glycol, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Triethanolamine, Beeswax, Tocopherol, Disodium EDTA, Stearic Acid, Myristyl Alcohol, Prunus Amygdalus Dulcis Oil, Prunus Armeniaca Kernel Oil, Persea Gratissima Oil 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. Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created. Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin. Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on). Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!). It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome. On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive. Another perk of this ingredient is that it stays functional across a wide pH range (3-10). You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own. Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU. Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages. Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon. Squalene is one of the main components of skin surface lipids. It is naturally found in our skin and makes up about 13% of sebum. Topically, it is an emollient and skin conditioning agent. Research highlights its role in antioxidant activity, anti-inflammatory effects, skin barrier protection, and wound healing support. In vivo research has shown that transepidermal water loss (TEWL) caused by irritant exposure can be reverse with squalene supplementation (pointing to barrier recovery support). Its antioxidant activity is backed by ex vivo and cell-based evidence showing it can scavenge free radicals but large-scale human clinical trials isolating this effect remain limited. One study found squalene regulated proinflammatory behavior in ways relevant to wound healing, and in vitro fibroblast studies also shows it stimulates cell migration which is a key step in skin repair. There's just one nuance to know about this ingredient: Squalene is particularly vulnerable to oxidation; it breaks down from UV exposure 10x faster than the other lipids on your skin's surface. The byproducts of that breakdown can clog pores and trigger