Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

Obagi Professional-C Serum 10% Versus Obagi Professional-C Serum 20%

Obagi Professional-C Serum 10% Versus Obagi Professional-C Serum 20% Detailed comparison of Obagi Professional-C Serum 10% versus Obagi Professional-C Serum 20%. This brightening serum is formulated around Ascorbic Acid to brighten dull-looking skin and soften

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Obagi Professional-C Serum 10% Versus Obagi Professional-C Serum 20% Detailed comparison of Obagi Professional-C Serum 10% versus Obagi Professional-C Serum 20%. This brightening serum is formulated around Ascorbic Acid to brighten dull-looking skin and soften the look of wrinkles. This brightening serum is formulated around Ascorbic Acid and Ascorbyl Glucoside to brighten dull-looking skin and soften the look of wrinkles. Propylene Glycol Water Propylene Carbonate Ascorbic Acid Parfum Propylene Glycol, Water, Propylene Carbonate, Ascorbic Acid, Parfum Alcohol Ascorbyl Glucoside Ethoxydiglycol Phenoxyethanol Sorbitol Sodium Hyaluronate Zinc Chloride Calcium Hydroxide Propylene Glycol, Water, Ascorbic Acid, Alcohol, Ascorbyl Glucoside, Ethoxydiglycol, Phenoxyethanol, Sorbitol, Sodium Hyaluronate, Zinc Chloride, Calcium Hydroxide, Parfum These ingredients are found in both products. Ingredients higher up in an ingredient list are typically present in a larger amount. Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin. Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for: Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently. One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin. While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects. The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption. Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits. Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day. Read more about other types of Vitamin C: Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients. 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 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 by INCI standards. One example is Calendula flower extract. Calendul