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Obagi Professional-C Serum 20% Versus Sunday Riley C.E.O. 15% Vitamin C Brightening Serum

Obagi Professional-C Serum 20% Versus Sunday Riley C.E.O. 15% Vitamin C Brightening Serum This brightening serum is formulated around Ascorbic Acid and Ascorbyl Glucoside to brighten dull-looking skin and soften the look of wrinkles. This brightening serum is

By Peptide Skincare & Beauty Editorial TeamPublished

Obagi Professional-C Serum 20% Versus Sunday Riley C.E.O. 15% Vitamin C Brightening Serum

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

This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Glycolic Acid to brighten dull-looking skin and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Propylene Glycol

Water

Ascorbic Acid

Alcohol

Ascorbyl Glucoside

Ethoxydiglycol

Phenoxyethanol

Sorbitol

Sodium Hyaluronate

Zinc Chloride

Calcium Hydroxide

Parfum

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

Tetrahexyldecyl Ascorbate

Squalane

Polyglyceryl-6 Distearate

PEG-8 Beeswax

PPG-12/Smdi Copolymer

Glycine Soja Sterols

Sodium Phytate

Tocopherol

Acetamidoethoxyethanol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Jojoba Esters

Glycolic Acid

Caprylyl Glycol

Cetyl Alcohol

Polyglyceryl-3 Beeswax

Chlorphenesin

Glycerin

Polysorbate 60

Sorbitan Isostearate

Saccharide Isomerate

Citrus Aurantium Dulcis Peel Oil

Citrus Tangerina Peel Oil

Linalool

Limonene

Water, Tetrahexyldecyl Ascorbate, Squalane, Polyglyceryl-6 Distearate, PEG-8 Beeswax, PPG-12/Smdi Copolymer, Glycine Soja Sterols, Sodium Phytate, Tocopherol, Acetamidoethoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Jojoba Esters, Glycolic Acid, Caprylyl Glycol, Cetyl Alcohol, Polyglyceryl-3 Beeswax, Chlorphenesin, Glycerin, Polysorbate 60, Sorbitan Isostearate, Saccharide Isomerate, Citrus Aurantium Dulcis Peel Oil, Citrus Tangerina Peel Oil, Linalool, Limonene, Phenoxyethanol

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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.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

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!

Similar Comparisons

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. 03Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.
  4. 04Not 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:
  5. 05Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.
  6. 06One 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.
  7. 07While 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.
  8. 08The 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% be…
  9. 09Skin 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.
  10. 10Ascorbic 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…
  11. 11Read more about other types of Vitamin C:
  12. 12Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.
  13. 13Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers.
  14. 14In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling
  15. 15This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA.
  16. 16It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper.
  17. 17The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it inter…
  18. 18Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product).
  19. 19Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare.
  20. 20Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye.
Source · skinsort.com ⟶
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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

Read side by side

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