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No7 Radiance+ 15% Vitamin C Serum Versus Obagi Professional-C Serum 20%

No7 Radiance+ 15% Vitamin C Serum Versus Obagi Professional-C Serum 20% This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and fade the look of dark spots. This brightening serum is formulated around Ascorbic Acid

No7 Radiance+ 15% Vitamin C Serum Versus Obagi Professional-C Serum 20%

This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and fade the look of dark spots.

This brightening serum is formulated around Ascorbic Acid and Ascorbyl Glucoside to brighten dull-looking skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

3-O-Ethyl Ascorbic Acid

Propylene Glycol

Polysorbate 20

Polyacrylate Crosspolymer-6

Ethylhexylglycerin

Sodium Hyaluronate

Benzyl Alcohol

Allantoin

Xanthan Gum

PEG-40 Hydrogenated Castor Oil

Sodium Citrate

Limonene

Dipropylene Glycol

Linalool

T-Butyl Alcohol

Parfum

Citric Acid

Denatonium Benzoate

Water, 3-O-Ethyl Ascorbic Acid, Propylene Glycol, Polysorbate 20, Polyacrylate Crosspolymer-6, Ethylhexylglycerin, Sodium Hyaluronate, Benzyl Alcohol, Allantoin, Xanthan Gum, PEG-40 Hydrogenated Castor Oil, Sodium Citrate, Limonene, Dipropylene Glycol, Linalool, T-Butyl Alcohol, Parfum, Citric Acid, Denatonium Benzoate

Ascorbic Acid

Alcohol

Ascorbyl Glucoside

Ethoxydiglycol

Phenoxyethanol

Sorbitol

Zinc Chloride

Calcium Hydroxide

Propylene Glycol, Water, Ascorbic Acid, Alcohol, Ascorbyl Glucoside, Ethoxydiglycol, Phenoxyethanol, Sorbitol, Sodium Hyaluronate, Zinc Chloride, Calcium Hydroxide, Parfum

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

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. Calendula is an essential oil that still imparts a scent or 'fragrance'.

Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.

Parfum can also be used to mask or cover an unpleasant scent.

The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.

Propylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.

As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.

The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

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The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Ascorbyl Glucoside (AA-2G) is one of the most stable vitamin C derivatives out there.
  4. 04It's made by attaching a glucose molecule to ascorbic acid; this glucose "cap" shields the vitamin C from air, light, heat, and metal ions that normally cause pure ascorbic acid to oxidize.
  5. 05Once on your skin, the enzyme alpha-glucosidase snips off the glucose and gradually releases active ascorbic acid right where it's needed. Basically, it behaves like a slow-release pro-vitamin C with less of a stinging that high-strength ascorbic ac…
  6. 06The research supports the classic vitamin C benefits as well. In lab and human studies, AA-2G slowed down the skin's production of melanin (the pigment behind dark spots) and helped shield skin cells against sun damage better than ascorbyl phosphate.
  7. 07These studies also showed AA-2G released vitamin C over a longer period.
  8. 08A frequently cited manufacturer trial found that a 2% AA-2G face cream significantly improved wrinkle depth and skin roughness after 45 days.
  9. 09And in 2009, a clinical trial showed it meaningfully lightened dark patches on the gums compared to a placebo.
  10. 10There's also collagen-synthesis support (since vitamin C is a required cofactor for that) and an antioxidant effect too.
  11. 11Typical usage is usually between 0.5-5% and most studies/products land around 2%.
  12. 12AA-2G performs best when formulated at a mildly acidic pH (~5-7) which is much gentler than the pH that pure vitamin C demands (~2.5-3.5).
  13. 13Just one thing worth knowing: the in-skin conversation rate is only about 55-60% by weight. So a 5% AA-2G product delivers roughly 2.75-3% of actual active vitamin C. On top of that, skin absorption is relatively low because the ingredient is water-…
  14. 14Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
  15. 15Also 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.
  16. 16For 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 regul…
  17. 17The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
  18. 18For 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.
  19. 19One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
  20. 20Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Source · skinsort.com
02

Product index

Related product references

Product

Obagi Professional-C Serum 20%

Obagi Professional-C Serum 20% Ingredients in Obagi Professional-C Serum 20% explained: benefits, concerns, and detailed analysis of 12 ingredients including Propylene Glycol, Water, and As…

Source: skinsort.comView reference →
03

Comparison edit

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