Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Paula's Choice C15 Super Booster Versus SkinBetter Science Alto Advanced Defense and Repair Serum

Paula's Choice C15 Super Booster Versus SkinBetter Science Alto Advanced Defense and Repair Serum Detailed comparison of Paula's Choice C15 Super Booster versus SkinBetter Science Alto Advanced Defense and Repair Serum. This brightening serum is formulated aro

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Paula's Choice C15 Super Booster Versus SkinBetter Science Alto Advanced Defense and Repair Serum Detailed comparison of Paula's Choice C15 Super Booster versus SkinBetter Science Alto Advanced Defense and Repair Serum. This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles. This barrier-repair serum is formulated around Niacinamide to strengthen the skin barrier and calm redness. Water Ascorbic Acid Dipropylene Glycol Propanediol Glycerin Ethoxydiglycol Sodium Hydroxide PPG-26-Buteth-26 PEG-40 Hydrogenated Castor Oil Bisabolol Ferulic Acid Sodium Phytate Decylene Glycol Tocopherol 1,2-Hexanediol Sphingomonas Ferment Extract Phenoxyethanol Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, Phenoxyethanol Butylene Glycol Ethylhexyl Olivate Cetearyl Alcohol Chlorogenic Acids Niacinamide Lauryl Lactate Dimethyl Isosorbide Pyrroloquinoline Quinone Allyl Ester Hydrolyzed Sodium Hyaluronate Glycyrrhiza Glabra Root Extract Tetrahexyldecyl Ascorbate Ergothioneine Benzylidene Dimethoxydimethylindanone Arabidopsis Thaliana Extract Carnosine Camellia Sinensis Leaf Extract Vitis Vinifera Seed Extract Theobroma Cacao Seed Extract Curcuma Longa Root Extract Olea Europaea Fruit Extract Euterpe Oleracea Fruit Extract Trifluoroacetyl Tripeptide-2 Buddleja Officinalis Flower Extract Coffea Arabica Leaf Cell Extract Crocus Sativus Leaf Cell Culture Extract Superoxide Dismutase Ubiquinone Plankton Extract Micrococcus Lysate Arginine Zingiber Officinale Root Extract Ceramide NP Ceramide AP Ceramide EOP Linoleic Acid Linolenic Acid Sea Whip Extract Tocopheryl Acetate Cholesterol Phytosphingosine Jojoba Esters Sodium PCA Pentylene Glycol Methyl Gluceth-20 Helianthus Annuus Seed Wax Acacia Decurrens Flower Wax Lecithin Sodium Lauroyl Lactylate Dicetyl Phosphate Propanediol Dicaprylate/Caprate Polyglycerin-3 Ceteth-20 Phosphate Diisostearyl Malate Xanthan Gum Steareth-2 Acacia Senegal Gum Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate Carbomer Acrylates/C10-30 Alkyl Acrylate Crosspolymer Dextran Ricinoleth-40 Citric Acid Ethylhexylglycerin Water, Butylene Glycol, Propanediol, Ethylhexyl Olivate, Cetearyl Alcohol, Chlorogenic Acids, Niacinamide, Lauryl Lactate, Dimethyl Isosorbide, Pyrroloquinoline Quinone Allyl Ester, Hydrolyzed Sodium Hyaluronate, Glycyrrhiza Glabra Root Extract, Tetrahexyldecyl Ascorbate, Ergothioneine, Benzylidene Dimethoxydimethylindanone, Arabidopsis Thaliana Extract, Carnosine, Camellia Sinensis Leaf Extract, Vitis Vinifera Seed Extract, Theobroma Cacao Seed Extract, Curcuma Longa Root Extract, Olea Europaea Fruit Extract, Euterpe Oleracea Fruit Extract, Trifluoroacetyl Tripeptide-2, Buddleja Officinalis Flower Extract, Coffea Arabica Leaf Cell Extract, Crocus Sativus Leaf Cell Culture Extract, Superoxide Dismutase, Ubiquinone, Plankton Extract, Micrococcus Lysate, Arginine, Zingiber Officinale Root Extract, Ceramide NP, Ceramide AP, Ceramide EOP, Linoleic Acid, Linolenic Acid, Sea Whip Extract, Bisabolol, Tocopherol, Tocopheryl Acetate, Cholesterol, Phytosphingosine, Jojoba Esters, Sodium PCA, Pentylene Glycol, Methyl Gluceth-20, Glycerin, Helianthus Annuus Seed Wax, Acacia Decurrens Flower Wax, Lecithin, These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient. It's primary claim to fame is soothing and research shows topically applied bisabolol can quiet the chemical messengers that cause your skin to become inflamed, helping to sooth any irritation. A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin. In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum. You'll likely see use concentrations quite low, usually 0.1-0.2%. Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin. 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. 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 t