Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

The INKEY List Caffeine Stimulating Scalp Treatment Versus The INKEY List Hyaluronic Acid Hydrating Hair Treatment

The INKEY List Caffeine Stimulating Scalp Treatment Versus The INKEY List Hyaluronic Acid Hydrating Hair Treatment Detailed comparison of The INKEY List Caffeine Stimulating Scalp Treatment versus The INKEY List Hyaluronic Acid Hydrating Hair Treatment. No con

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The INKEY List Caffeine Stimulating Scalp Treatment Versus The INKEY List Hyaluronic Acid Hydrating Hair Treatment Detailed comparison of The INKEY List Caffeine Stimulating Scalp Treatment versus The INKEY List Hyaluronic Acid Hydrating Hair Treatment. No concerns Water Betaine Caffeine Panthenol Phenoxyethanol Glycerin Xanthan Gum Ethylhexylglycerin Trisodium Ethylenediamine Disuccinate Lactic Acid Sodium Metabisulfite Glycine Larix Europaea Wood Extract Camellia Sinensis Extract Zinc Chloride Water, Betaine, Caffeine, Panthenol, Phenoxyethanol, Glycerin, Xanthan Gum, Ethylhexylglycerin, Trisodium Ethylenediamine Disuccinate, Lactic Acid, Sodium Metabisulfite, Glycine, Larix Europaea Wood Extract, Camellia Sinensis Extract, Zinc Chloride PEG-40 Hydrogenated Castor Oil Polyquaternium-37 Citronellyl Methylcrotonate Hydrolyzed Hyaluronic Acid Sodium Hyaluronate Water, PEG-40 Hydrogenated Castor Oil, Betaine, Panthenol, Phenoxyethanol, Polyquaternium-37, Citronellyl Methylcrotonate, Ethylhexylglycerin, Hydrolyzed Hyaluronic Acid, Trisodium Ethylenediamine Disuccinate, Lactic Acid, Sodium Hyaluronate These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. It’s known for being gentle and for helping the skin maintain balanced hydration. Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte. Some studies suggest betaine may support making skin tone more even. Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability. Betaine is also known as trimethylglycine. Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that: The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure. Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations. Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective. Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin. Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin. Like glycolic acid, it can: Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate. Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome. To get results, choose products with a pH between 3-4. Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time. Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations. When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH. Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles. Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshnes