Peptide Skincare & BeautySkin science and ingredient guides

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The Ordinary Multi-Peptide Serum for Hair Density Versus The Ordinary Amino Acids + B5

The Ordinary Multi-Peptide Serum for Hair Density Versus The Ordinary Amino Acids + B5 Detailed comparison of The Ordinary Multi-Peptide Serum for Hair Density versus The Ordinary Amino Acids + B5. This hydrating serum is formulated around Sodium PCA and Panth

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The Ordinary Multi-Peptide Serum for Hair Density Versus The Ordinary Amino Acids + B5 Detailed comparison of The Ordinary Multi-Peptide Serum for Hair Density versus The Ordinary Amino Acids + B5. This hydrating serum is formulated around Sodium PCA and Panthenol to hydrate skin and strengthen the skin barrier. No key ingredients Water Propanediol Butylene Glycol Glycerin Caffeine Biotinoyl Tripeptide-1 Acetyl Tetrapeptide-3 Larix Europaea Wood Extract Pisum Sativum Extract Scutellaria Baicalensis Root Extract Triticum Vulgare Germ Extract Glycine Soja Germ Extract Trifolium Pratense Flower Extract Camellia Sinensis Leaf Extract Apigenin Oleanolic Acid Arginine Glycine Calcium Gluconate Zinc Chloride Lactic Acid Gluconolactone Dextran Maltodextrin Hydroxyethylcellulose Xanthan Gum Pentylene Glycol Dimethyl Isosorbide Polysorbate 20 PPG-26-Buteth-26 PEG-40 Hydrogenated Castor Oil Trisodium Ethylenediamine Disuccinate Sodium Metabisulfite Sodium Benzoate Phenoxyethanol Chlorphenesin Water, Propanediol, Butylene Glycol, Glycerin, Caffeine, Biotinoyl Tripeptide-1, Acetyl Tetrapeptide-3, Larix Europaea Wood Extract, Pisum Sativum Extract, Scutellaria Baicalensis Root Extract, Triticum Vulgare Germ Extract, Glycine Soja Germ Extract, Trifolium Pratense Flower Extract, Camellia Sinensis Leaf Extract, Apigenin, Oleanolic Acid, Arginine, Glycine, Calcium Gluconate, Zinc Chloride, Lactic Acid, Gluconolactone, Dextran, Maltodextrin, Hydroxyethylcellulose, Xanthan Gum, Pentylene Glycol, Dimethyl Isosorbide, Polysorbate 20, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Trisodium Ethylenediamine Disuccinate, Sodium Metabisulfite, Sodium Benzoate, Phenoxyethanol, Chlorphenesin Betaine Sodium PCA Panthenol Sodium Lactate PCA Aspartic Acid Alanine Serine Threonine Valine Proline Isoleucine Lysine Hcl Histidine Phenylalanine Glutamic Acid Citric Acid 1,2-Hexanediol Caprylyl Glycol Water, Propanediol, Betaine, Sodium PCA, Panthenol, Sodium Lactate, Arginine, PCA, Aspartic Acid, Glycine, Alanine, Serine, Threonine, Valine, Proline, Isoleucine, Lysine Hcl, Histidine, Phenylalanine, Glutamic Acid, Citric Acid, Dimethyl Isosorbide, Polysorbate 20, Trisodium Ethylenediamine Disuccinate, 1,2-Hexanediol, Caprylyl Glycol These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources. It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy. Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces. A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks. Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis. One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies. Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne. Dimethyl Isosorbide (often shortened to DMI) is a sugar-derived solvent made from sorbitol. It's used to dissolve tricky ingredients and help them mix smoothly into a formula. Many actives sit as gritty crystals when undissolved, so DMI swoops in to full dissolve them. This helps improve texture, stability, and how evenly an active is distributed. It does have a penetration-enhancing reputation that is a bit more nuanced than marketing suggests; a cell study on human skin found that 10% DMI didn't significantly boost the permeation of Hydroquinone, Salicylic Acid, or Octadecenedioic Acid compared to controls (though it did improve their solubility in the formula itself). Typical usage concentrations usually range from 1-10% depending on the formula's needs; this ingredient is also well tolerated at these levels. Glycine is the smallest amino acid and a key building block of collagen. It's part if your skin's Natural Moisturizing Factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy. A study from 2022 found that an amino acid complex featuring taurine, arginine, and glycine significantly reduced skin irritation, improved redness, and accelerated the skin repair process. Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable. It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better. The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane. Trace amounts can form during production but the EU's Scien