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The Ordinary Retinol 0.2% In Squalane Versus Paula's Choice 1% Retinol Booster

The Ordinary Retinol 0.2% In Squalane Versus Paula's Choice 1% Retinol Booster This anti-aging serum is formulated around Squalane and Retinol to soften the look of wrinkles and refine skin texture. This anti-aging treatment is formulated around Retinol and Ce

The Ordinary Retinol 0.2% In Squalane Versus Paula's Choice 1% Retinol Booster

This anti-aging serum is formulated around Squalane and Retinol to soften the look of wrinkles and refine skin texture.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Squalane

Caprylic/Capric Triglyceride

Simmondsia Chinensis Seed Oil

Retinol

Solanum Lycopersicum Fruit Extract

Rosmarinus Officinalis Leaf Extract

Hydroxymethoxyphenyl Decanone

BHT

Squalane, Caprylic/Capric Triglyceride, Simmondsia Chinensis Seed Oil, Retinol, Solanum Lycopersicum Fruit Extract, Rosmarinus Officinalis Leaf Extract, Hydroxymethoxyphenyl Decanone, BHT

Water

Glycerin

Carthamus Tinctorius Seed Oil

Polyglyceryl-10 Caprylate/Caprate

Butylene Glycol

Pyrus Malus Fruit Extract

Polysorbate 20

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

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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.

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.

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The reference edit

Ingredients, questions
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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. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  7. 07Topically, glycerin does several things at once:
  8. 08Your 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.
  9. 09Aquaporin-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.
  10. 10This 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.
  11. 11Just know very high concentrations (>40%) can feel tacky in low humidity.
  12. 12Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  13. 13Hexylene Glycol is a multitasker ingredient that works as a solvent, humectant, emulsifier, viscosity reducer, and preservative booster.
  14. 14It is able to dissolve both water and oil-soluble ingredients to stabilize tricky actives and make products spread more easily.
  15. 15As a humectant, it pulls water into the skin. But it's a pretty minor moisturizing ingredient compared to other humectants, like glycerin.
  16. 16Interestingly, 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%.
  17. 17This ingredient is typically used at levels of 0.1-10% depending on the role it's playing.
  18. 18A 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.
  19. 19Water. 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.
  20. 20So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
Source · skinsort.com
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