Obagi Professional-C Serum 20% Review

Obagi Professional-C Serum 20%
5.0
/ 10
Moisturizing
10.0 Humectancy icon Humectancy
0.0 Occlusivity icon Occlusivity
2.5Anti-wrinkle icon/ 10
Anti-wrinkle
Rich
in Antioxidants
Review

Does Obagi Professional-C Serum 20% Work?

 
According to CreamScan AI's analysis of the ingredient list, here’s what Obagi Professional-C Serum 20% has to offer:
 
✅ Strong humectant moisturizing. This lightweight, humectant-rich product, ideal for oily skin, has a moisturizing rating of 5.0 out of 10.
✅ Modest anti-wrinkle efficacy: Obagi Professional-C Serum 20% has an anti-wrinkle rating of 2.5 out of 10 so you may expect some, although limited, effect on wrinkles.
✅ Antioxidant protection

  

Key Benefits of Obagi Professional-C Serum 20%

 
These are the key benefits you can expect from using Obagi Professional-C Serum 20%:
 

🔵 Lightweight Purely Humectant Moisturizing, Ideal for Oily Skin

According to CreamScan analysis, Obagi Professional-C Serum 20% is quite moisturizing, with a moisturizing rating of 5.0 out of 10.

Is it more humectant or occlusive? Question icon The Humectancy (from 0 to 10) is based on the amount of humectants in the formula and indicates how well the product can attract moisture to the skin. Humectants are effective moisturizers that work well for all skin types. The Occlusivity (from 0 to 10) is based on the amount of occlusives in the formula and indicates how effective the product is at sealing moisture into the skin. Occlusive moisturizers are ideal for those with dry skin. Question icon The Humectancy (from 0 to 10) is based on the amount of humectants in the formula and indicates how well the product can attract moisture to the skin. Humectants are effective moisturizers that work well for all skin types. The Occlusivity (from 0 to 10) is based on the amount of occlusives in the formula and indicates how effective the product is at sealing moisture into the skin. Occlusive moisturizers are ideal for those with dry skin. It is purely humectant. It has zero occlusivity (we didn't find any occlusive ingredients on the ingredient list) and a maximum humectancy of 10 out of 10, primarily due to the high content of Propylene Glycol (est. ≈40.0%) and Ethoxydiglycol (est. ≈3.0%).

This humectant-rich product, when used alone as a moisturizer, is ideal for oily skin, providing significant hydration in a lightweight, fast-absorbing formula without any occlusive ingredients.

📌 Certain studies suggest that humectants alone may not effectively moisturize the skin. If you use this product as your only moisturizer, we recommend following it with one that contains at least some occlusive ingredients.

💧 A Humectant Boost for Any Skincare Routine

But it’s not limited to oily skin - such a humectant boost will also positively contribute to the moisturizing efficacy of any skincare routine when used as a step before applying the main moisturizer. This type of formulation is typically used in serums, where a light, fast-absorbing texture is key.

Please refer to the Ratings section below for details of the moisturizing rating calculation.

🟣 Modest Anti-Wrinkle Efficacy

According to CreamScan analysis, Obagi Professional-C Serum 20% has a modest level of anti-wrinkle efficacy, rated 2.5 out of 10.

It contains one ingredient with proven anti-wrinkle efficacy: Ascorbic Acid (est. ≈20.0%),
 or Vitamin C, a popular ingredient, yet with moderate anti-wrinkle efficacy, as confirmed by a single clinical study involving 20 participants (Humbert et al.). This study showed that a cream with a relatively high concentration of 5% ascorbic acid reduced the average wrinkle depth by 7% after 6 months of use, compared to a vehicle (the same formulation without ascorbic acid).
 
Among others, Obagi Professional-C Serum 20% also contains Ascorbyl Glucoside, an ingredient often marketed as effective in reducing wrinkles. However, the studies supporting the anti-wrinkle claims of Ascorbyl Glucoside provide insufficient evidence of its efficacy according to CreamScan Research Evaluation Standards.
 
While this does not categorically rule out the possibility that Ascorbyl Glucoside may reduce wrinkles, its efficacy is not supported by convincing, vehicle-controlled, double-blind clinical studies - at least none that were available to the CreamScan team at the time of publication.
 
Therefore, this ingredient does not contribute to the anti-wrinkle rating.
 
📌 Moisturizers, when used regularly, are proven to prevent wrinkle formation and even reduce existing wrinkles. Therefore, this product, like any other moisturizer, can deliver some additional anti-wrinkle effects through its moisturizing action.
 

Please refer to the Ratings section below for details of the anti-wrinkle rating calculation.

🍀 Rich in Skin-Protecting Antioxidants

We estimate that Obagi Professional-C Serum 20% is rich (> 3%) in antioxidants, specifically Ascorbic Acid (est. ≈20.0%) and Ascorbyl Glucoside (est. ≈4.0%).

A key benefit of antioxidants is their ability to reduce oxidative stress caused by free radicals and therefore prevent accelerated skin aging. Studies also show that antioxidants can protect against environmental damage such as UV radiation and pollution, and help reduce inflammation and skin redness.

📌 Please note that this is not a complete list of benefits. We are in the process of enhancing our AI model to incorporate anti-pigmentation, exfoliation and anti-acne ratings.

Things to Be Aware Of: Obagi Professional-C Serum 20%

 
CreamScan AI identified a few things to consider before adding Obagi Professional-C Serum 20% to your skincare routine:
 

⚠️ If It’s Your Only Moisturizer, It Needs to Be Paired with Some Occlusives

While humectants are highly effective at attracting water to the skin, studies (J. N. Kraft, C. W. Lynde) suggest they may not be efficient when used alone.

One major drawback of purely humectant moisturization is that the water attracted by humectants to the upper layers of the skin can evaporate completely into the environment through transepidermal water loss (TEWL). Adding occlusive ingredients helps seal this moisture into the skin and prevent further water loss.

If you’re using Obagi Professional-C Serum 20% as your only moisturizer, consider pairing it with one that contains at least some occlusive ingredients, such as oils, butters, or silicones. These work alongside humectants to create a protective barrier, locking in hydration and ensuring longer-lasting moisturization. The amount of occlusive needed depends on your skin type - the drier the skin, the more occlusives it requires.

If this product is used not as a standalone moisturizer but as part of your skincare routine, such as a toner or serum, it should be applied before your main moisturizer (unless it's a sunscreen), which will provide the necessary occlusivity on top of it.

Pros & Cons of Obagi Professional-C Serum 20%

 
Here’s an overview of the pros and cons of Obagi Professional-C Serum 20% to help you decide if it’s the right choice for your skincare routine:
 

🟩 Pros:

✅ When used alone: Provides humectant-rich moisturizing ideal for oily skin
✅ As part of a routine: A humectant moisturizing boost, beneficial for any skin type
✅ Lightweight texture
Offers modest anti-wrinkle efficacy
✅ Rich in antioxidants that combat oxidative stress associated with accelerated skin aging and defend against environmental damage
 

⭕ Cons: 

⚠️ Only if used as a standalone moisturizer - it needs to be paired with occlusives to seal in humectants
   

Summary: Obagi Professional-C Serum 20%

 
Based on the ingredient list analysis, CreamScan AI suggests that Obagi Professional-C Serum 20%
, when used alone, delivers lightweight, humectant-rich moisturizing, making it ideal for oily skin. As part of a moisturizing routine, it provides a humectant boost, beneficial for all skin types.
 
Obagi Professional-C Serum 20% contains ingredients with proven evidence of anti-wrinkle efficacy that may provide a modest anti-wrinkle effect. As a result, you can expect a positive, though not very significant, impact on wrinkles.
 
With its high antioxidant content, Obagi Professional-C Serum 20% helps protect against free radical damage and offers multiple benefits for all skin types, including preventing premature aging, defending against environmental damage, and calming inflammation.
 
That said, there are some things about Obagi Professional-C Serum 20% worth noting.
 
Looking at its moisturizing profile, we found that it doesn’t contain any occlusive ingredients, potentially allowing the moisture attracted to the skin by humectants to evaporate. Therefore, if it’s used as the only moisturizer in a routine, it’s recommended to pair it with one that contains at least some occlusive ingredients, such as oils, butters, or silicones.
 
📌 Fact check. At CreamScan, we are committed to accuracy and fairness. If you spot any errors or something that doesn’t seem right, please click here to let us know. We regularly update the ingredient lists and monitor the latest research on ingredient efficacy to ensure that our information remains as complete and precise as possible. The information provided here is for informational purposes only and does not substitute professional advice. We do not guarantee the efficacy or safety of any product, as individual results may vary.

 

Ingredients

Est. % Ingredient Origin Functions
40
22
20
6
4
3
1
1
1
0.3
0.3
0.3
Est. %
Propylene Glycol
Function:
Origin:
Water
Function:
Origin:
Ascorbic Acid
Function:
Origin:
Alcohol
Function:
Origin:
Ascorbyl Glucoside
Function:
Origin:
Ethoxydiglycol
Function:
Origin:
Phenoxyethanol
Function:
Origin:
Sorbitol
Function:
Origin:
Sodium Hyaluronate
Function:
Origin:
Zinc Chloride
Function:
Origin:
Calcium Hydroxide
Function:
Origin:
Fragrance
Function:
Origin:

Ratings

All humectants
45.0
40
3
1
1
Benchmark
10
All occlusives
0.0
None
Benchmark
20
Moisturizing rating
5.0
Ingredient Est. % Benchmark Raiting
Humectancy All humectants 45 10
10.0
40
3
1
1
Occlusivity All occlusives 0.0 20
0.0
None
Moisturizing rating
5.0
Ingredient Est. % Benchmark Humectancy
40
3
1
1
All humectants 45 10
10
All humectants
45.0
40
3
1
1
Benchmark
10
Ingredient Est. % Benchmark Occlusivity
None
All occlusives 0.0 20
0.0
All occlusives
0.0
None
Benchmark
20
Ingredient
Ingredient anti-wrinkle power
when present at, %
in this formula est. %
Rating
2.5 /10 5 20 2.5
n/a
- 4 -
Total
2.5
Ascorbic Acid
2.5
Ingredient anti-wrinkle power
2.5 /10
when present at, %
5
in this formula, est. %
20
Ascorbyl Glucoside
-
Ingredient anti-wrinkle power
n/a
when present at, %
-
in this formula, est. %
4
Anti-wrinkle rating
2.5
Ingredient Est. % Benchmark
Rich in Antioxidants
20
4
1
All antioxidants 25 3 Rich in antioxidants
All antioxidants
25
Ascorbic Acid
20
Ascorbyl Glucoside
4
Sodium Hyaluronate
1
Benchmark
3
Ingredient Est. % Benchmark
Rich in Soothing
0.3
All soothing 0.3 5 No
All soothing
0.3
0.3
Benchmark
5

Ingredients explained

Propylene Glycol
Est. %40
Function
Origin
Propylene GlycolA clear, thick, odorless liquid of synthetic origin. Its main function is to stabilize cosmetic products exposed to varying temperatures. It is also a moderately strong humectant with similar properties to glycerin.
Water
Est. %22
Function
Origin
WaterThe most used ingredient in skincare. Its concentration defines the product texture: rich creams may have about 50% of water while a light jelly about 90%. Water doesn’t moisturize the skin by itself and is used in skincare as a solvent for other ingredients.
Ascorbic Acid
Est. %20
Function
Origin
Ascorbic Acid

Also known as vitamin C, this multi-benefit ingredient has proven anti-wrinkle, antioxidant, and anti-pigmentation efficacy. It degrades easily when exposed to air and light, so it requires proper packaging to maintain its stability.

Alcohol
Est. %6
Function
Origin
AlcoholAn effective antimicrobial ingredient that kills bacteria, fungi, and even some viruses. It is also an excellent solvent and astringent. Alcohol helps to create lighter and less viscous products. It can, however, be dehydrating and skin-sensitizing.
Ascorbyl Glucoside
Est. %4
Function
Origin
Ascorbyl GlucosideA derivative of vitamin C. It is more stable and less irritating than ascorbic acid. There are unfortunately no clinical studies on ascorbyl glucoside’s anti-pigment or anti-acne efficacy alone.
Ethoxydiglycol
Est. %3
Function
Origin
EthoxydiglycolA type of alcohol with humectant moisturizing properties. It also acts as a solvent, since it mixes well with a variety of other compounds, including water and even some oils.
Phenoxyethanol
Est. %1
Function
Origin
PhenoxyethanolThe most frequently used preservative in skincare. It is a clear, oil-like liquid synthetic substance that protects products from harmful bacteria and yeast, whilst still leaving skin microflora unharmed. It is confirmed by research to be harmless.
Sorbitol
Est. %1
Function
Origin
SorbitolA sweet-tasting alcohol derived from glucose. Aside from its sweet taste (for which it is used as a very common sweetener), Sorbitol is also very good at retaining water and is used in skincare as a humectant.
Sodium Hyaluronate
Est. %1
Function
Origin
Sodium Hyaluronate

A sodium salt of famous hyaluronic acid. A potent humectant that hydrates the skin, supports collagen function, and fills out small wrinkles. Sodium hyaluronate also offers soothing and antioxidant properties.

Zinc Chloride
Est. %0.3
Function
Origin
Zinc Chloride
Calcium Hydroxide
Est. %0.3
Function
Origin
Calcium Hydroxide
Fragrance
Est. %0.3
Function
Origin
FragranceUnder trade secret law, manufacturers have the right not to disclose what exactly went into the fragrance and use the unspecific word Fragrance or Parfum instead. Many fragrances are highly allergenic.