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Paula's Choice Resist Optimal Results Hydrating Cleanser Versus Kiehl's Ultra Facial Cleanser

Paula's Choice Resist Optimal Results Hydrating Cleanser Versus Kiehl's Ultra Facial Cleanser This mild cream cleanser is made to cleanse without leaving your skin tight or dry. What's inside Key Ingredients No key ingredients Benefits Concerns Ingredients Sid

Paula's Choice Resist Optimal Results Hydrating Cleanser Versus Kiehl's Ultra Facial Cleanser

This mild cream cleanser is made to cleanse without leaving your skin tight or dry.

What's inside

Key Ingredients

No key ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Caprylic/Capric Triglyceride

Decyl Glucoside

Glycerin

PEG-20 Methyl Glucose Sesquistearate

PPG-20 Methyl Glucose Ether

Methyl Gluceth-20

Glyceryl Stearate

Stearyl Alcohol

Polyacrylamide

Camellia Oleifera Seed Oil

Chamomilla Recutita Flower Extract

Sapindus Mukorossi Peel Extract

Methyl Glucose Sesquistearate

C13-14 Isoparaffin

Laureth-7

Xanthan Gum

Disodium EDTA

Citric Acid

Caprylyl Glycol

Hexylene Glycol

Phenoxyethanol

Ethylhexylglycerin

Water, Caprylic/Capric Triglyceride, Decyl Glucoside, Glycerin, PEG-20 Methyl Glucose Sesquistearate, PPG-20 Methyl Glucose Ether, Methyl Gluceth-20, Glyceryl Stearate, Stearyl Alcohol, Polyacrylamide, Camellia Oleifera Seed Oil, Chamomilla Recutita Flower Extract, Sapindus Mukorossi Peel Extract, Methyl Glucose Sesquistearate, C13-14 Isoparaffin, Laureth-7, Xanthan Gum, Disodium EDTA, Citric Acid, Caprylyl Glycol, Hexylene Glycol, Phenoxyethanol, Ethylhexylglycerin

Sodium Laureth Sulfate

Cocamidopropyl Betaine

Disodium Cocoamphodiacetate

Acrylates Copolymer

Lauryl Glucoside

PEG-200 Hydrogenated Glyceryl Palmate

Triethanolamine

Sodium Chloride

Pentylene Glycol

PEG-7 Glyceryl Cocoate

Sodium Hydroxide

Behenyl Alcohol

Distearyl Ether

Sodium Benzoate

Laureth-2

Squalane

Prunus Amygdalus Dulcis Oil

Prunus Armeniaca Kernel Oil

Tocopherol

Ascorbyl Glucoside

Persea Gratissima Oil

Water, Sodium Laureth Sulfate, Decyl Glucoside, Glycerin, Cocamidopropyl Betaine, Disodium Cocoamphodiacetate, Acrylates Copolymer, Lauryl Glucoside, PEG-200 Hydrogenated Glyceryl Palmate, Triethanolamine, Sodium Chloride, Pentylene Glycol, Phenoxyethanol, PEG-7 Glyceryl Cocoate, Sodium Hydroxide, Citric Acid, Hexylene Glycol, Behenyl Alcohol, Distearyl Ether, Sodium Benzoate, Laureth-2, Squalane, Prunus Amygdalus Dulcis Oil, Prunus Armeniaca Kernel Oil, Tocopherol, Ascorbyl Glucoside, Persea Gratissima Oil

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Decyl Glucoside is a plant-derived surfactant and emulsion stabilizer. It is created by reacting glucose with the fatty acids from plants.

Like all surfactants, it works by lowering the surface tension between water and oil. This makes it so that dirt, sebum, and makeup can be lifted off your skin and rinsed away. It also produces a dense and creamy foam.

Because it has a neutral charge, it is compatible with a wide range of ingredients and stays stable across a broad pH range/water hardiness conditions.

Patch testing has shown it to have the lowest irritation potential among common cleansing surfactants (like SLS).

Typical use levels range from 5-20% in rinse-off cleansers.

One thing worth knowing: The American Contact Dermatitis Society named the parent family, alkyl glucosides, "Allergen of the Year" in 2017. The prevalence of allergy is pretty low but be sure to patch test if you've reacted to "gentle" or sulfate-free cleansers before.

This ingredient is fungal acne safe because the fatty alcohol portion of this ingredient is not within the C11-24 chain length that Malassezia can metabolize.

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.

Hexylene Glycol is a multitasker ingredient that works as a solvent, humectant, emulsifier, viscosity reducer, and preservative booster.

It is able to dissolve both water and oil-soluble ingredients to stabilize tricky actives and make products spread more easily.

As a humectant, it pulls water into the skin. But it's a pretty minor moisturizing ingredient compared to other humectants, like glycerin.

Interestingly, it can act as a mild penetration enhancer. One in vitro study on human skin found a 12% concentration upped the absorption of mometasone furoate (a medicinal ingredient used to treat inflammatory skin conditions) up to 7%.

This ingredient is typically used at levels of 0.1-10% depending on the role it's playing.

A patch test study on eczema patients didn't find a significant increase in irritation versus the control group, but the potential for irritation rises at higher concentrations.

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!

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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 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. 03Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.
  4. 04The way it works is fairly well mapped out:
  5. 05Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down o…
  6. 06The clinical backing is pretty solid too.
  7. 07A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at…
  8. 08A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
  9. 09On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.
  10. 10This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
  11. 11Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
  12. 12C12-15 Alkyl Benzoate is a lightweight emollient made by combinig benzoic acid with fatty alcohols that are 12-15 carbons long.
  13. 13In cosmetics, it plays several roles:
  14. 14The Cosmetic Review Expert Panel has concluded the alkyl benzoate group to be safe as used in cosmetics; it wasn't found to be a skin irritant and unlikely to be absorbed due to its low water solubility.
  15. 15This report recorded almost 1000 reported uses with concentrations up to 59% in leave-on products but your cosmetics will typically use 0.5-15% depending on the product.
  16. 16It's often called a "SPF booster": this is because it keeps UV filters properly dissolved and evenly distributed to support a sunscreen's performance. It doesn't actually raise SPF on its own.
  17. 17Overall, this ingredient is well tolerated.
  18. 18This ingredient is fungal acne safe because it is an ester of benzoic acid.
  19. 19Think of this ingredient as two parts stuck together: an oily part and an acid part. Malassezia only gets a meal when it can snip off a fatty acid to eat. With C12-15 Alkyl Benzoate, the acid part is benzoic acid, which isn't a fatty acid and which …
  20. 20Benzoic acid is actually used as a preservative to stop yeast from growing.
Source · skinsort.com
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