Kiehl's Nightly Refining Micro-Peel Concentrate Review

Kiehl's Nightly Refining Micro-Peel Concentrate
2.2
/ 10
Moisturizing
4.5 Humectancy icon Humectancy
0.0 Occlusivity icon Occlusivity
Review

Does Kiehl's Nightly Refining Micro-Peel Concentrate Work?

 
According to CreamScan AI's analysis of the ingredient list, here’s what Kiehl's Nightly Refining Micro-Peel Concentrate has to offer:
 
✅ Light moisturizing. It has a moisturizing rating of 2.2 out of 10.

  

Key Benefits of Kiehl's Nightly Refining Micro-Peel Concentrate

 
These are the key benefits you can expect from using Kiehl's Nightly Refining Micro-Peel Concentrate:
 

🔵 Lightweight Purely Humectant Moisturizer Suitable for Oily Skin

According to CreamScan analysis, Kiehl's Nightly Refining Micro-Peel Concentrate is lightly moisturizing, with a moisturizing rating of 2.2 out of 10.

Is it more humectant or occlusive? Purely humectant. It has zero occlusivity (we didn't find any occlusive ingredients on the ingredient list) and a moderate humectancy of 4.5 out of 10, primarily due to the high content of Hydroxyethyl Urea (est. ≈3.0%).

This product, when used alone as a moisturizer, can provide light humectant hydration in a fast-absorbing formula without any occlusive ingredients. This could work for people with oily skin who need a basic level of hydration.

📌 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 Add-on for Any Skincare Routine

But it’s not limited to oily skin - since it contains a moderate amount of humectants, such a humectant add-on will also positively contribute to the moisturizing efficacy of any skincare routine when used as a step before applying the main moisturizer.

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

📌 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: Kiehl's Nightly Refining Micro-Peel Concentrate

 
CreamScan AI identified a few things to consider before adding Kiehl's Nightly Refining Micro-Peel Concentrate 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 Kiehl's Nightly Refining Micro-Peel Concentrate 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.

⚠️ Questionable anti-wrinkle efficacy

If one of your main reasons for choosing Kiehl's Nightly Refining Micro-Peel Concentrate is its potential anti-aging effects, please note that, according to CreamScan analysis, it currently has a zero anti-wrinkle rating.

It contains Adenosine and Ascorbyl Glucoside, two ingredients often marketed as effective in reducing wrinkles. However, the studies supporting the anti-wrinkle claims of these ingredients provide insufficient evidence of efficacy according to CreamScan Research Evaluation Standards.

While this does not categorically rule out the possibility that these ingredients may reduce wrinkles, their 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, these ingredients do not generate 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 anti-wrinkle effects through its moisturizing action.

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

Pros & Cons of Kiehl's Nightly Refining Micro-Peel Concentrate

 
Here’s an overview of the pros and cons of Kiehl's Nightly Refining Micro-Peel Concentrate to help you decide if it’s the right choice for your skincare routine:
 

🟩 Pros:

✅ When used alone: Provides moderate humectant moisturizing suitable for oily skin
✅ As part of a routine: A humectant moisturizing enhancement, beneficial for any skin type
✅ Lightweight texture
 

⭕ Cons: 

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

Summary: Kiehl's Nightly Refining Micro-Peel Concentrate

 
Based on the ingredient list analysis, CreamScan AI suggests that Kiehl's Nightly Refining Micro-Peel Concentrate
, when used alone, provides lightweight, moderate humectant moisturizing, making it suitable for oily skin. As part of a moisturizing routine, it offers a subtle humectant enhancement, beneficial for all skin types.
 
That said, there are some things about Kiehl's Nightly Refining Micro-Peel Concentrate 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.
 
If one of your main reasons for considering Kiehl's Nightly Refining Micro-Peel Concentrate is its potential anti-aging effects, please note that, according to CreamScan analysis, its anti-wrinkle efficacy is questionable. None of the ingredients in this product provide substantial evidence of their anti-wrinkle efficacy according to CreamScan Research Evaluation Standards.
 
📌 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
75
6
4
3
2
1.5
1.3
1
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
0.3
Est. %
Water
Function:
Origin:
Alcohol Denat.
Function:
Origin:
Hydroxyethylpiperazine Ethane Sulfonic Acid
Function:
Origin:
Hydroxyethyl Urea
Function:
Origin:
Sodium Citrate
Function:
Origin:
Vaccinium Myrtillus Fruit Extract
Function:
Origin:
Sodium Hydroxide
Function:
Origin:
Chenopodium Quinoa Seed Extract
Function:
Origin:
Saccharum Officinarum (Sugarcane) Extract
Function:
Origin:
Glycerin
Function:
Origin:
Propanediol
Function:
Origin:
Phytic Acid
Function:
Origin:
Carrageenan
Function:
Origin:
Phenoxyethanol
Function:
Origin:
Olea Europaea (Olive) Fruit Water
Function:
Origin:
Citrus Limon (Lemon) Fruit Extract
Function:
Origin:
Disodium EDTA
Function:
Origin:
Acer Saccharum (Sugar Maple) Extract
Function:
Origin:
Hydrolyzed Opuntia Ficus-Indica Flower Extract
Function:
Origin:
Potassium Sorbate
Function:
Origin:
Aloe Barbadensis Leaf Juice Powder
Function:
Origin:
Adenosine
Function:
Origin:
Ethylhexylglycerin
Function:
Origin:
Citrus Aurantium Dulcis (Orange) Peel Oil
Function:
Origin:
Sodium Benzoate
Function:
Origin:
Ascorbyl Glucoside
Function:
Origin:

Ratings

All humectants
4.5
3
0.3
0.3
0.3
0.3
0.3
Benchmark
10
All occlusives
0.0
None
Benchmark
20
Moisturizing rating
2.2
Ingredient Est. % Benchmark Raiting
Humectancy All humectants 4.5 10
4.5
3
0.3
0.3
0.3
0.3
0.3
Occlusivity All occlusives 0.0 20
0.0
None
Moisturizing rating
2.2
Ingredient Est. % Benchmark Humectancy
3
0.3
0.3
0.3
0.3
0.3
All humectants 4.5 10
4.5
All humectants
4.5
3
0.3
0.3
0.3
0.3
0.3
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
n/a
- 0.3 -
n/a
- 0.3 -
Total
0
Adenosine
-
Ingredient anti-wrinkle power
n/a
when present at, %
-
in this formula, est. %
0.3
Ascorbyl Glucoside
-
Ingredient anti-wrinkle power
n/a
when present at, %
-
in this formula, est. %
0.3
Anti-wrinkle rating
0
Ingredient Est. % Benchmark
Rich in Antioxidants
1.5
0.3
0.3
0.3
All antioxidants 2.4 3 No
All antioxidants
2.4
Vaccinium Myrtillus Fruit Extract
1.5
Saccharum Officinarum (Sugarcane) Extract
0.3
Acer Saccharum (Sugar Maple) Extract
0.3
Ascorbyl Glucoside
0.3
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

Water
Est. %75
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.
Alcohol Denat.
Est. %6
Function
Origin
Alcohol Denat.

Denatured alcohol is ethanol that contains additives that make it unsafe to consume. It is mainly used as a solvent and an antimicrobial agent. A major drawback to alcohol denat. is that it dries out the skin.

Hydroxyethylpiperazine Ethane Sulfonic Acid
Est. %4
Function
Origin
Hydroxyethylpiperazine Ethane Sulfonic AcidA pH buffer that secures the pH around 7.5.
Hydroxyethyl Urea
Est. %3
Function
Origin
Hydroxyethyl UreaHydroxyethyl urea is a synthetic derivative of regular urea (read about it here). This ingredient, similarly to urea, is humectant moisturizing and helps to retain more water to the skin’s surface, leaving it more moisturized. There aren't any studies that analyze the effects of this ingredient in great detail.
Sodium Citrate
Est. %2
Function
Origin
Sodium CitrateA salt of citric acid that has a salty and tart flavor and is used as a fragrance. It is mildly basic, meaning that its addition to a skincare product can adjust the pH upward.
Vaccinium Myrtillus Fruit Extract
Est. %1.5
Function
Origin
Vaccinium Myrtillus Fruit ExtractAn extract derived from the berries of the bilberry plant, sometimes called European blueberry. It is rich in antioxidant anthocyanins and astringent tannins.
Sodium Hydroxide
Est. %1.3
Function
Origin
Sodium Hydroxide

An ingredient that is able to bring the pH of a product up, thereby making it less harsh on the skin.

Chenopodium Quinoa Seed Extract
Est. %1
Function
Origin
Chenopodium Quinoa Seed ExtractDerived from quinoa seeds, the extract contains various emollient phytochemicals such as phytosterols, saponins, proteins, and amino acids.
Saccharum Officinarum (Sugarcane) Extract
Est. %0.3
Function
Origin
Saccharum Officinarum (Sugarcane) ExtractAn antioxidant extract from sugarcane, the famous crop used to make sugar. It acts as a humectant and exfoliating agent – the little sugar crystals mechanically remove dead skin cells from the skin’s surface.
Glycerin
Est. %0.3
Function
Origin
Glycerin

The most popular moisturizing ingredient in the world. It is a powerful humectant – cheap yet very effective.

Propanediol
Est. %0.3
Function
Origin
PropanediolAn excellent solvent capable of mixing water with normally water-insoluble ingredients. It also functions as a humectant due to its water-loving alcohol groups. Propanediol can control the viscosity of a product by reducing its thickness.
Phytic Acid
Est. %0.3
Function
Origin
Phytic AcidPhytic acid is found in rice and is seen as a cousin of alpha-hydroxy acids. As a chelator, it can bind to certain metals that may cause discoloration in products or reduce the efficacy of other ingredients.
Carrageenan
Est. %0.3
Function
Origin
CarrageenanA gum-like thickener derived from a species of red algae called Irish moss. It helps to form a soft film on the skin, and aids in stabilizing product forms.
Phenoxyethanol
Est. %0.3
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.
Olea Europaea (Olive) Fruit Water
Est. %0.3
Function
Origin
Olea Europaea (Olive) Fruit Water
Citrus Limon (Lemon) Fruit Extract
Est. %0.3
Function
Origin
Citrus Limon (Lemon) Fruit Extract

A fragrant extract from lemon peels that contains various antioxidant flavonoids, organic acids, and limonoids – which are currently under investigation as potential anti-wrinkle and anti-pigment compounds.

Disodium EDTA
Est. %0.3
Function
Origin
Disodium EDTAA synthetic chelator that helps to maintain the look and smell of a product by 'locking up' troublesome metal ions.
Acer Saccharum (Sugar Maple) Extract
Est. %0.3
Function
Origin
Acer Saccharum (Sugar Maple) ExtractAn antioxidant extract from sugar maple bark and sap – the same sweet sap used to make maple syrup. It has a faint vanilla smell and is used in skincare for its exfoliating properties. This is because of the small sugar crystals present in the extract.
Hydrolyzed Opuntia Ficus-Indica Flower Extract
Est. %0.3
Function
Origin
Hydrolyzed Opuntia Ficus-Indica Flower Extract
Potassium Sorbate
Est. %0.3
Function
Origin
Potassium SorbateA preservative widely used in food and personal care products, available from natural sources or synthetically produced. Potassium sorbate works by inhibiting the growth of yeasts, molds, and some bacteria.
Aloe Barbadensis Leaf Juice Powder
Est. %0.3
Function
Origin
Aloe Barbadensis Leaf Juice PowderExtracted from dried aloe vera leaves, it has the same effects as fresh aloe vera juice – it is humectant moisturizing, refreshing, and soothing. This powder can also serve as a gelling agent when mixed with water.
Adenosine
Est. %0.3
Function
Origin
Adenosine

A key molecule responsible for energy transportation, signaling, and enzyme activity. Adenosine is a popular anti-wrinkle ingredient, however, the key study about its anti-wrinkle efficacy (1) does not meet CreamScan Research Evaluation Standards as it is not double-blind.

Ethylhexylglycerin
Est. %0.3
Function
Origin
EthylhexylglycerinA preservative booster derived from glycerin. It is commonly paired with other preservatives to improve their efficacy. Ethylhexylglycerin is also a humectant due to its chemical base of glycerin.
Citrus Aurantium Dulcis (Orange) Peel Oil
Est. %0.3
Function
Origin
Citrus Aurantium Dulcis (Orange) Peel Oil

An essential oil derived from the peels of the sweet orange. It is commonly used as a fragrance because of its pleasant, citrusy scent. The main constituent of the essential oil is limonene (up to 96%).

Sodium Benzoate
Est. %0.3
Function
Origin
Sodium BenzoateA preservative that usually works in combination with other preservatives. It has to be at low pH (<5.5) to be effective.
Ascorbyl Glucoside
Est. %0.3
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.