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Paula's Choice 1% Retinol Booster Versus The INKEY List Retinol Eye Cream

Paula's Choice 1% Retinol Booster Versus The INKEY List Retinol Eye Cream This anti-aging treatment is formulated around Retinol and Ceramide NP to soften the look of wrinkles and refine skin texture. This anti-aging eye moisturizer is formulated around Retino

Paula's Choice 1% Retinol Booster Versus The INKEY List Retinol Eye Cream

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

This anti-aging eye moisturizer is formulated around Retinol and Sodium Hyaluronate to soften the look of wrinkles and refine skin texture.

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

Caprylic/Capric Triglyceride

Pentaerythrityl Distearate

Shea Butter Ethyl Esters

Cetearyl Olivate

Benzyl Alcohol

Sorbitan Olivate

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Sodium Hydroxide

Sodium Hyaluronate

Sodium Stearoyl Glutamate

Copernicia Cerifera Cera

Propanediol

Glycogen

Sodium Gluconate

Ethylhexylglycerin

Dehydroacetic Acid

Citric Acid

Helianthus Annuus Seed Oil

1,2-Hexanediol

Disodium Cocoamphodiacetate

Tocopherol

Ethyl Ferulate

Humulus Lupulus Extract

Water, Caprylic/Capric Triglyceride, Glycerin, Butylene Glycol, Pentaerythrityl Distearate, Shea Butter Ethyl Esters, Cetearyl Olivate, Phenoxyethanol, Benzyl Alcohol, Sorbitan Olivate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Hydroxide, Sodium Hyaluronate, Sodium Stearoyl Glutamate, Copernicia Cerifera Cera, Propanediol, Glycogen, Sodium Gluconate, Retinol, Polysorbate 20, Ethylhexylglycerin, Dehydroacetic Acid, Citric Acid, Helianthus Annuus Seed Oil, 1,2-Hexanediol, Caprylyl Glycol, Disodium Cocoamphodiacetate, Tocopherol, Xanthan Gum, Ethyl Ferulate, Humulus Lupulus Extract

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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.

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.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

Retinol is one of the most studied anti-aging ingredients in skincare (and for good reason!).

It's a form of vitamin A that your skin converts into Retinoic Acid, the active molecule that actually does the work in your cells.

That conversion happens in two steps: your skin first turns Retinol into Retinaldehyde (also called Retinal), then turns Retinaldehyde into Retinoic Acid.

Retinol is converted to biologically active retinoic acid via retinaldehyde by dehydrogenases in a two-step oxidation process.

Each step is a little "upgrade" toward the active form which is part of why Retinol is gentler than prescription Retinoic Acid; your skin does the work gradually. This also explains where Retinol sits in the retinoid family.

Here is the retinoid family ranked roughly by strength: Retinyl Esters (like Retinyl Palmitate) < Retinol < Retinaldehyde < Retinoic Acid.

Retinoid activity increases in that order, while tolerance runs in reverse; retinyl esters are the gentlest and retinoic acid the most irritating.

The more conversion steps an ingredient needs, the gentler (and slower) it tends to be, so Retinol lands in a nice middle spot. It's more effective than the esters, gentler than prescription options.

Once it becomes Retinoic Acid, it binds to receptors inside your cells' nuclei (called RARs and RXRs). These receptor pairs bind to specific DNA motifs called retinoic acid response elements and act like switches that turn certain genes on or off.

In practice, this means a few things happen in a formula. It:

That last two are worth a closer look.

A study that tested Retinol directly (not just prescription Retinoic Acid) found that four weeks of retinol thickened the epidermis and switched on the genes for Collagen I and Collagen III, with more procollagen I and III showing up in the skin. And after twelve weeks, facial wrinkles were visibly reduced.

Retinoids more broadly stimulate the skin's synthesis of hyaluronan and other glycosaminoglycans, part of what gives skin a plumper, more hydrated look over time.

So even the gentler OTC form is doing real structural work (not just sitting on the surface).

It's also worth knowing Retinol isn't only a wrinkle ingredient; it can help with uneven tone, dark spots, rough texture, and the look of pores as well because it speeds up turnover and influences pigment.

The research backs this up as well.

A pooled analysis of six clinical studies found that 0.1% stabilized retinol improved all signs of photoaging versus vehicle as early as week 4 and through 12 weeks, with only a few mild cases of irritation.

Another study comparing concentrations found that 0.3% and 1% Retinol were similarly effective at remodeling photodamaged skin, but 0.3% caused fewer adverse reactions when used daily (a useful reminder that more isn't always better).

Retinol is about tenfold less potent than Retinoic Acid. This is why it works as a gentler, non-prescription option that builds results over time.

Typical concentrations range from 0.1-1%, with 0.1% to 0.3% being a well-supported sweet spot for visible benefits with good tolerability.

One quirk worth mentioning: Retinol is famously unstable.

It's highly sensitive to light and oxygen, and UV exposure breaks it down into a range of degradation products.

Real-world testing bears this out, with retinoid content in some products dropping anywhere from 0% to 80% after six months at room temperature, and even more at higher temperatures.

This is why good formulations lean on opaque, air-tight packaging (think tubes and pumps, not clear jars) and often "encapsulate" the Retinol to shield it.

Signs of oxidation include your product turning yellow or smelling "off". Keeping it somewhere cool and dark, and using it up within a few months of opening helps it stay effective.

The most common side effects are mild and temporary: usually some dryness, redness, or light peeling as your skin adjusts. These tend to settle with consistent and lower-frequency use.

Like all retinoids, Retinol works best with nightly use, a good moisturizer, and daytime sunscreen.

The "ramp up" method works well: start with Retinol once a week to give your skin time to adjust, which keeps irritation low. Slowly add more nights until you reach your goal frequency once your skin feels comfortable.

Retinoids also make your skin more sensitive to the sun in the first few weeks, so wear sunscreen every morning and protect your skin from direct sun while you build up tolerance.

One safety note: topical Retinoids aren't recommended during pregnancy or breastfeeding. Systemic absorption from creams is low but because high oral vitamin A is a known teratogen and topical safety data are limited, most clinicians recommend stopping retinoids when pregnant or trying to conceive.

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 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. 03Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.
  4. 04It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.
  5. 05Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.
  6. 06A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.
  7. 07Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.
  8. 08One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.
  9. 09Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.
  10. 10Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.
  11. 11You'll often see this ingredient paired with other ceramides (like ceramide NP), cholesterol, or fatty acids because this combination best mimics the natural lipid mix your skin already has.
  12. 12The skin's ability to produce ceramides gets disrupted in skin conditions like eczema. This in turn weakens the skin barrier and applying ceramides topically has been shown to replenish what's been lost to restore barrier function.
  13. 13Most of the studies with Ceramide AP test it as part of a multi-ceramide complex; studies reinforce ceramide AP's role in rebalancing ceramides in skin and improving skin hydration.
  14. 14Ceramide EOP is formally known as Ceramide 1.
  15. 15It is naturally found in skin and part of the intercellular "mortar" holding everything together in your outermost layer.
  16. 16EOP stands for a linked Ester fatty acid, a linked Omega hydroxy fatty acid, and the Phytosphingosine base.
  17. 17What makes Ceramide EOP special is its ultra-long fatty acid chain; this unique structure allows it to bridge the lipid layers in your skin barrier to prevent water loss (something no other ceramide can do).
  18. 18Low levels of Ceramide EOP have been found in people with eczema and psoriasis.
  19. 19Using it together with other ceramides, cholesterol, and linoleic acid have been shown to meaningfully improve hydration and reduce water loss.
  20. 20In one clinical study, a regimen using Ceramide EOP, NP, and AP led to significant symptom improvements in patients with eczema, psoriasis, and dry skin in just 4 weeks.
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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