Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

REDKEN Extreme Length Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo

REDKEN Extreme Length Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo Detailed comparison of REDKEN Extreme Length Shampoo versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo. Water Sodium Laureth Sulfate Sodium Chloride Cocamidopropyl Betain

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REDKEN Extreme Length Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo Detailed comparison of REDKEN Extreme Length Shampoo versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo. Water Sodium Laureth Sulfate Sodium Chloride Cocamidopropyl Betaine Citric Acid Sodium Hydroxide Parfum Propylene Glycol Polyquaternium-10 Sodium Benzoate Hexylene Glycol Salicylic Acid Benzyl Benzoate Limonene Benzyl Alcohol Linalool 2-Oleamido-1,3-Octadecanediol Biotin Water, Sodium Laureth Sulfate, Sodium Chloride, Cocamidopropyl Betaine, Citric Acid, Sodium Hydroxide, Parfum, Propylene Glycol, Polyquaternium-10, Sodium Benzoate, Hexylene Glycol, Salicylic Acid, Benzyl Benzoate, Limonene, Benzyl Alcohol, Linalool, 2-Oleamido-1,3-Octadecanediol, Biotin Sodium C14-16 Olefin Sulfonate Cocamidopropyl Hydroxysultaine Charcoal Powder Sh-Oligopeptide-78 Panthenol Glycerin Sodium Phytate Guar Hydroxypropyltrimonium Chloride Caprylyl Glycol Caprylhydroxamic Acid Potassium Hydroxide Benzyl Salicylate Water, Sodium C14-16 Olefin Sulfonate, Cocamidopropyl Hydroxysultaine, Salicylic Acid, Charcoal Powder, Sh-Oligopeptide-78, Panthenol, Glycerin, Sodium Phytate, Guar Hydroxypropyltrimonium Chloride, Caprylyl Glycol, Caprylhydroxamic Acid, Citric Acid, Potassium Hydroxide, Sodium Hydroxide, Parfum, Benzyl Salicylate, Limonene 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. 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. Limonene is a fragrance that adds scent and taste to a formulation. It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus". Limonene acts as an antioxidant, meaning it helps neutralize free radicals. When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin. The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance. Parfum is a catch-all term for an ingredient or more that is used to give a scent to products. Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture. For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations. The term 'parfum' or 'fragrance' is not regulated in many c