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Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide Versus Disciple Shadow Work AHA/BHA Serum

Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide Versus Disciple Shadow Work AHA/BHA Serum This anti-aging serum is formulated around Niacinamide and Ceramide NP to soften the look of wrinkles and refine skin texture. This smoothing serum

Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide Versus Disciple Shadow Work AHA/BHA Serum

This anti-aging serum is formulated around Niacinamide and Ceramide NP to soften the look of wrinkles and refine skin texture.

This smoothing serum is formulated around Glycolic Acid and Salicylic Acid to refine skin texture and clear breakouts.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Butylene Glycol

Pentylene Glycol

Niacinamide

Cetyl Alcohol

Isohexadecane

Isononyl Isononanoate

Diisopropyl Sebacate

2-Oleamido-1,3-Octadecanediol

4-T-Butylcyclohexanol

Acetyl Dipeptide-1 Cetyl Ester

Adenosine

Ceramide NP

Hydroxypalmitoyl Sphinganine

Lauroyl Lysine

Octyldodecanol

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Sodium Chloride

Sodium Hyaluronate

Sodium Hydroxide

Trisodium Ethylenediamine Disuccinate

Retinol

Tocopherol

Dicaprylyl Ether

Ammonium Polyacryloyldimethyl Taurate

Behenyl Alcohol

Caprylyl Glycol

Carbomer

Cetearyl Alcohol

Cetearyl Glucoside

Glycine Soja Oil

Helianthus Annuus Seed Oil

Hydroxyethylcellulose

Lecithin

Phenethyl Alcohol

Poloxamer 188

Polycaprolactone

Sorbitan Laurate

Steareth-100

CI 40800

Chlorphenesin

Phenoxyethanol

Water, Glycerin, Butylene Glycol, Pentylene Glycol, Niacinamide, Cetyl Alcohol, Isohexadecane, Isononyl Isononanoate, Diisopropyl Sebacate, 2-Oleamido-1,3-Octadecanediol, 4-T-Butylcyclohexanol, Acetyl Dipeptide-1 Cetyl Ester, Adenosine, Ceramide NP, Hydroxypalmitoyl Sphinganine, Lauroyl Lysine, Octyldodecanol, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Chloride, Sodium Hyaluronate, Sodium Hydroxide, Trisodium Ethylenediamine Disuccinate, Retinol, Tocopherol, Dicaprylyl Ether, Ammonium Polyacryloyldimethyl Taurate, Behenyl Alcohol, Caprylyl Glycol, Carbomer, Cetearyl Alcohol, Cetearyl Glucoside, Glycine Soja Oil, Helianthus Annuus Seed Oil, Hydroxyethylcellulose, Lecithin, Phenethyl Alcohol, Poloxamer 188, Polycaprolactone, Sorbitan Laurate, Steareth-100, CI 40800, Chlorphenesin, Phenoxyethanol

Glycolic Acid

Propylene Glycol

Hydroxyacetophenone

Salicylic Acid

Amylopectin

Dextrin

Xanthan Gum

Sodium Polyacrylate

Disodium Phosphate

Polysorbate 60

CI 16255

Sodium Phosphate

CI 42090

Water, Glycerin, Glycolic Acid, Hydroxyethylcellulose, Propylene Glycol, Hydroxyacetophenone, Phenoxyethanol, Salicylic Acid, Amylopectin, Dextrin, Xanthan Gum, Sodium Polyacrylate, Disodium Phosphate, Polysorbate 60, CI 16255, Sodium Phosphate, CI 42090

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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.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

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.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Glycerin
  3. 03Butylene Glycol
  4. 04Pentylene Glycol
  5. 05Niacinamide
  6. 06Cetyl Alcohol
  7. 07Isohexadecane
  8. 08Isononyl Isononanoate
  9. 09Diisopropyl Sebacate
  10. 102-Oleamido-1,3-Octadecanediol
  11. 114-T-Butylcyclohexanol
  12. 12Acetyl Dipeptide-1 Cetyl Ester
  13. 13Adenosine
  14. 14Ceramide NP
  15. 15Hydroxypalmitoyl Sphinganine
  16. 16Lauroyl Lysine
  17. 17Octyldodecanol
  18. 18Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate
  19. 19Sodium Chloride
  20. 20Sodium Hyaluronate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side