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Paula's Choice 1% Retinol Booster Versus Kiehl's Fast Release Wrinkle-Reducing 0.3% Retinol Night Serum

Paula's Choice 1% Retinol Booster Versus Kiehl's Fast Release Wrinkle-Reducing 0.3% Retinol Night Serum This anti-aging treatment is formulated around Retinol and Ceramide NP to soften the look of wrinkles and refine skin texture. This anti-aging serum is form

Paula's Choice 1% Retinol Booster Versus Kiehl's Fast Release Wrinkle-Reducing 0.3% Retinol Night Serum

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

This anti-aging serum is formulated around Panthenol and Adenosine to soften the look of wrinkles and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Carthamus Tinctorius Seed Oil

Polyglyceryl-10 Caprylate/Caprate

Butylene Glycol

Pyrus Malus Fruit Extract

Polysorbate 20

Retinol

Glycyrrhiza Glabra Root

Ceramide NP

Palmitoyl Tripeptide-1

Avena Sativa Kernel Extract

Epilobium Angustifolium Extract

Arctium Lappa Seed Oil

Salix Alba Extract

Allantoin

Dipotassium Glycyrrhizate

Caprylyl Glycol

Polyglyceryl-10 Laurate

Dipentaerythrityl Hexacaprylate/Hexacaprate

Ethylhexyl Olivate

Hydrogenated Lecithin

Glyceryl Ascorbate

Disodium EDTA

Sorbic Acid

Xanthan Gum

Phenoxyethanol

Water, Glycerin, Carthamus Tinctorius Seed Oil, Polyglyceryl-10 Caprylate/Caprate, Butylene Glycol, Pyrus Malus Fruit Extract, Polysorbate 20, Retinol, Glycyrrhiza Glabra Root, Ceramide NP, Palmitoyl Tripeptide-1, Avena Sativa Kernel Extract, Epilobium Angustifolium Extract, Arctium Lappa Seed Oil, Salix Alba Extract, Allantoin, Dipotassium Glycyrrhizate, Caprylyl Glycol, Polyglyceryl-10 Laurate, Dipentaerythrityl Hexacaprylate/Hexacaprate, Ethylhexyl Olivate, Hydrogenated Lecithin, Glyceryl Ascorbate, Disodium EDTA, Sorbic Acid, Xanthan Gum, Phenoxyethanol

Propanediol

Glycereth-26

Panthenol

1,2-Hexanediol

Polyglycerin-3

C12-14 Pareth-12

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Betaine

Ethylhexylglycerin

Adenosine

Carbomer

Glyceryl Acrylate/Acrylic Acid Copolymer

Tromethamine

Glycereth-25 PCA Isostearate

T-Butyl Alcohol

Tocopherol

Water, Glycerin, Propanediol, Butylene Glycol, Glycereth-26, Panthenol, 1,2-Hexanediol, Polyglycerin-3, C12-14 Pareth-12, Phenoxyethanol, Caprylyl Glycol, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Betaine, Xanthan Gum, Ethylhexylglycerin, Adenosine, Carbomer, Glyceryl Acrylate/Acrylic Acid Copolymer, Tromethamine, Glycereth-25 PCA Isostearate, T-Butyl Alcohol, Tocopherol

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

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.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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. 02C12-15 Alkyl Benzoate
  3. 03Zinc Oxide
  4. 04Titanium Dioxide
  5. 05Glycerin
  6. 06Isononyl Isononanoate
  7. 07Butylene Glycol
  8. 08Cetearyl Alcohol
  9. 09Potassium Cetyl Phosphate
  10. 10Dimethicone
  11. 11Glyceryl Stearate
  12. 12Glycyrrhiza Glabra Root Extract
  13. 13Actinidia Chinensis Fruit Extract
  14. 14Argania Spinosa Kernel Oil
  15. 15Tetrapeptide-30
  16. 16Linoleic Acid
  17. 17Resveratrol
  18. 18Ascorbyl Glucoside
  19. 19Niacinamide
  20. 20Tocopheryl Acetate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side