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Skin science article

Paula's Choice Retinol Skin-Smoothing Body Treatment Versus Naturium Retinol Complex Serum

Paula's Choice Retinol Skin-Smoothing Body Treatment Versus Naturium Retinol Complex Serum This smoothing moisturizer is formulated around Retinol and Tetrahexyldecyl Ascorbate to refine skin texture and soften the look of wrinkles. This anti-aging serum is fo

Paula's Choice Retinol Skin-Smoothing Body Treatment Versus Naturium Retinol Complex Serum

This smoothing moisturizer is formulated around Retinol and Tetrahexyldecyl Ascorbate to refine skin texture and soften the look of wrinkles.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Cetearyl Alcohol

Cetearyl Ethylhexanoate

Cyclopentasiloxane

Dimethicone

Glycerin

Butylene Glycol

Cetyl Palmitate

Butyrospermum Parkii Butter

Glyceryl Stearate

PEG-100 Stearate

Oenothera Biennis Oil

Vitis Vinifera Seed Oil

Cetyl Alcohol

Retinol

Tetrahexyldecyl Ascorbate

Tocopheryl Acetate

Caprylic/Capric Triglyceride

Panthenol

Carnosine

Dimethiconol

Dimethicone/Vinyl Dimethicone Crosspolymer

Beeswax

Magnesium Aluminum Silicate

Sodium Hydroxide

Xanthan Gum

Dicaprylyl Carbonate

Decylene Glycol

Disodium EDTA

Chlorphenesin

Phenoxyethanol

Water, Cetearyl Alcohol, Cetearyl Ethylhexanoate, Cyclopentasiloxane, Dimethicone, Glycerin, Butylene Glycol, Cetyl Palmitate, Butyrospermum Parkii Butter, Glyceryl Stearate, PEG-100 Stearate, Oenothera Biennis Oil, Vitis Vinifera Seed Oil, Cetyl Alcohol, Retinol, Tetrahexyldecyl Ascorbate, Tocopheryl Acetate, Caprylic/Capric Triglyceride, Panthenol, Carnosine, Dimethiconol, Dimethicone/Vinyl Dimethicone Crosspolymer, Beeswax, Magnesium Aluminum Silicate, Sodium Hydroxide, Xanthan Gum, Dicaprylyl Carbonate, Decylene Glycol, Disodium EDTA, Chlorphenesin, Phenoxyethanol

Propanediol

Astrocaryum Murumuru Seed Butter

Gossypium Herbaceum Fruit Water

Bakuchiol

Bidens Pilosa Extract

Linum Usitatissimum Seed Oil

Humulus Lupulus Extract

Sodium Hyaluronate

Tocopherol

Caprylyl Glycol

Helianthus Annuus Seed Oil

Copernicia Cerifera Wax

Carbomer

Potassium Sorbate

Disodium Cocoamphodiacetate

Hexylene Glycol

Citric Acid

Polysorbate 20

Glyceryl Polyacrylate

1,2-Hexanediol

Ethyl Ferulate

Water, Propanediol, Astrocaryum Murumuru Seed Butter, Gossypium Herbaceum Fruit Water, Retinol, Glycerin, Bakuchiol, Bidens Pilosa Extract, Linum Usitatissimum Seed Oil, Humulus Lupulus Extract, Sodium Hyaluronate, Tocopherol, Caprylyl Glycol, Helianthus Annuus Seed Oil, Copernicia Cerifera Wax, Phenoxyethanol, Carbomer, Potassium Sorbate, Xanthan Gum, Disodium Cocoamphodiacetate, Hexylene Glycol, Citric Acid, Sodium Hydroxide, Polysorbate 20, Glyceryl Polyacrylate, 1,2-Hexanediol, Ethyl Ferulate

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.

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.

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.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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. 02Glycerin
  3. 03Dimethicone
  4. 04Butylene Glycol
  5. 05Propanediol
  6. 06Stearic Acid
  7. 07Glyceryl Stearate
  8. 08Isohexadecane
  9. 09Potassium PCA
  10. 10Magnesium PCA
  11. 11Calcium PCA
  12. 12Ethylhexyl Olivate
  13. 13Polyglyceryl-4 Olivate
  14. 14Pyrus Malus Fruit Extract
  15. 15Laminaria Saccharina Extract
  16. 16Actinidia Chinensis Fruit Extract
  17. 17Coffea Arabica Seed Extract
  18. 18Biotin/Folic Acid/Cyanocobalamin/Niacinamide/Pantothenic Acid/Pyridoxine/Riboflavin/Thiamine/Yeast Polypeptides
  19. 19Garcinia Mangostana Peel Extract
  20. 20Prunus Serotina Fruit Extract
Source · skinsort.com
02

Product index

Related product references

Product

Paula's Choice The Unscrub

Paula's Choice The Unscrub Paula's Choice The Unscrub ingredients explained: Aqua (Water), Jojoba Esters (Cleansing Beads), Caprylic/Capric Triglyceride (Skin-Replenishing), Glycerin (Skin …

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side