Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Peter Thomas Roth Instant FIRMx Eye™ Versus Q + A Peptide Serum

Peter Thomas Roth Instant FIRMx Eye™ Versus Q + A Peptide Serum Detailed comparison of Peter Thomas Roth Instant FIRMx Eye™ versus Q + A Peptide Serum. This anti-aging eye moisturizer is formulated around Palmitoyl Tetrapeptide-7 and Dipeptide-2 to soften the

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Peter Thomas Roth Instant FIRMx Eye™ Versus Q + A Peptide Serum Detailed comparison of Peter Thomas Roth Instant FIRMx Eye™ versus Q + A Peptide Serum. This anti-aging eye moisturizer is formulated around Palmitoyl Tetrapeptide-7 and Dipeptide-2 to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated around Aloe Barbadensis Leaf Juice Powder and Tripeptide-29 to soften the look of wrinkles and hydrate skin. Water Glycerin Butylene Glycol Sodium Silicate Magnesium Aluminum Silicate Sodium Magnesium Fluorosilicate Palmitoyl Tetrapeptide-7 Dipeptide-2 Ascorbic Acid Tocopheryl Acetate Hesperidin Methyl Chalcone Retinyl Palmitate Panthenol Foeniculum Vulgare Seed Extract Medicago Sativa Seed Extract Carrageenan Argania Spinosa Kernel Extract PEG-8 Dimethicone Silica Octyldodecanol Symphytum Officinale Leaf Extract Sodium Propoxyhydroxypropyl Thiosulfate Silica BHT Disodium EDTA Hydrolyzed Lupine Protein Steareth-20 Sodium Cocoyl Glutamate Carbomer Chlorhexidine Digluconate Ethylhexylglycerin Potassium Sorbate Citric Acid Sodium Citrate Sodium Benzoate Phenoxyethanol Water, Glycerin, Butylene Glycol, Sodium Silicate, Magnesium Aluminum Silicate, Sodium Magnesium Fluorosilicate, Palmitoyl Tetrapeptide-7, Dipeptide-2, Ascorbic Acid, Tocopheryl Acetate, Hesperidin Methyl Chalcone, Retinyl Palmitate, Panthenol, Foeniculum Vulgare Seed Extract, Medicago Sativa Seed Extract, Carrageenan, Argania Spinosa Kernel Extract, PEG-8 Dimethicone, Silica, Octyldodecanol, Symphytum Officinale Leaf Extract, Sodium Propoxyhydroxypropyl Thiosulfate Silica, BHT, Disodium EDTA, Hydrolyzed Lupine Protein, Steareth-20, Sodium Cocoyl Glutamate, Carbomer, Chlorhexidine Digluconate, Ethylhexylglycerin, Potassium Sorbate, Citric Acid, Sodium Citrate, Sodium Benzoate, Phenoxyethanol Propylene Glycol Betaine Pentylene Glycol Xanthan Gum Aloe Barbadensis Leaf Juice Powder Sodium Phytate Lonicera Caprifolium Flower Extract Biosaccharide Gum-1 Lonicera Japonica Flower Extract Sodium Levulinate Tripeptide-29 Sodium Hyaluronate Sodium Ascorbyl Phosphate Magnesium PCA Lactic Acid Glyceryl Caprylate Cocoyl Proline Sodium Anisate Leuconostoc/Radish Root Ferment Filtrate Water, Propylene Glycol, Betaine, Pentylene Glycol, Xanthan Gum, Aloe Barbadensis Leaf Juice Powder, Sodium Phytate, Glycerin, Lonicera Caprifolium Flower Extract, Biosaccharide Gum-1, Lonicera Japonica Flower Extract, Sodium Levulinate, Tripeptide-29, Sodium Hyaluronate, Sodium Ascorbyl Phosphate, Magnesium PCA, Lactic Acid, Glyceryl Caprylate, Cocoyl Proline, Sodium Anisate, Leuconostoc/Radish Root Ferment Filtrate, Citric Acid These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes. Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath. However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products. Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH. In skincare formulas, citric acid can: While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants. Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations. Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger. However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure. 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. Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product. So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation. You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!