Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Pureology Pure Volume Shampoo Versus K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo

Pureology Pure Volume Shampoo Versus K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo Detailed comparison of Pureology Pure Volume Shampoo versus K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo. Water Cocamidopropyl Betaine Disodium Laureth Sulfosuccinate Sodium La

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Pureology Pure Volume Shampoo Versus K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo Detailed comparison of Pureology Pure Volume Shampoo versus K18 Hair PEPTIDE PREP™ pH Maintenance Shampoo. Water Cocamidopropyl Betaine Disodium Laureth Sulfosuccinate Sodium Lauryl Sulfoacetate Sodium Lauroyl Sarcosinate Sodium Chloride Glycol Distearate PPG-5-Ceteth-20 Sodium Polystyrene Sulfonate Decyl Glucoside Parfum Citric Acid Sodium Hydroxide Sodium Benzoate Carbomer PEG-55 Propylene Glycol Oleate Propylene Glycol Coco-Betaine PEG-150 Pentaerythrityl Tetrastearate Salicylic Acid PEG-6 Caprylic/Capric Glycerides Glycerin Butylene Glycol Benzoic Acid Tocopherol Hydroxypropyltrimonium Hydrolyzed Wheat Protein Helianthus Annuus Seed Extract Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol Limonene Benzophenone-4 Citronellol Eucalyptus Globulus Leaf Extract Phenoxyethanol CI 17200 Potassium Sorbate Water, Cocamidopropyl Betaine, Disodium Laureth Sulfosuccinate, Sodium Lauryl Sulfoacetate, Sodium Lauroyl Sarcosinate, Sodium Chloride, Glycol Distearate, PPG-5-Ceteth-20, Sodium Polystyrene Sulfonate, Decyl Glucoside, Parfum, Citric Acid, Sodium Hydroxide, Sodium Benzoate, Carbomer, PEG-55 Propylene Glycol Oleate, Propylene Glycol, Coco-Betaine, PEG-150 Pentaerythrityl Tetrastearate, Salicylic Acid, PEG-6 Caprylic/Capric Glycerides, Glycerin, Butylene Glycol, Benzoic Acid, Tocopherol, Hydroxypropyltrimonium Hydrolyzed Wheat Protein, Helianthus Annuus Seed Extract, Hydrolyzed Vegetable Protein Pg-Propyl Silanetriol, Limonene, Benzophenone-4, Citronellol, Eucalyptus Globulus Leaf Extract, Phenoxyethanol, CI 17200, Potassium Sorbate Sodium C14-16 Olefin Sulfonate Sodium Methyl 2-Sulfolaurate Sh-Oligopeptide-78 Panthenol Sodium Phytate Guar Hydroxypropyltrimonium Chloride Disodium 2-Sulfolaurate Caprylyl Glycol Caprylhydroxamic Acid Water, Sodium C14-16 Olefin Sulfonate, Cocamidopropyl Betaine, Sodium Methyl 2-Sulfolaurate, Sodium Lauryl Sulfoacetate, Sh-Oligopeptide-78, Panthenol, Glycerin, Sodium Phytate, Guar Hydroxypropyltrimonium Chloride, Disodium 2-Sulfolaurate, Caprylyl Glycol, Caprylhydroxamic Acid, Benzoic Acid, Citric Acid, Sodium Hydroxide, Parfum, Limonene These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Benzoic Acid is an organic acid that shows up in cosmetics as a preservative. It helps keep a product from spoiling by holding back the growth of yeast, mold, and some bacteria. This ingredient also functions as a fragrance ingredient that helps mask the unpleasant scent of other ingredients. The way it works is worth understanding; benzoic acid works when the formula is acidic. It is able to sneak into a microbe's cell and mess up how it functions to stop it from growing in an acidic product. However, the acid switches to an inactive form and stops working if a product isn't acidic enough (above ~5 pH). This is why you'll often see it in low pH products or teamed up with other preservatives to cover the gap. Safety wise, it's one of the better studied preservatives out there. The Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe for use in cosmetic formulations at concentrations up to 5%. A large international review found this ingredient had no effects on the human body and had low irritation potential. Just so you know, real world use is usually much lower than the 5% ceiling (usually 1% of less). The EU caps it at 2.5% in rinse-off products, 1.7% in oral care, and 0.5% in leave-on products. One thing worth mentioning (it's nothing to worry about): some people get a little stinging or flushing where they apply it. This isn't a true allergy; it's a temporary and harmless reaction. This is the same kind of mild tingle you might notice from sorbic acid. 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 e