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Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum Versus CeraVe Skin Renewing Retinol Serum

Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum Versus CeraVe Skin Renewing Retinol Serum This anti-aging serum is formulated around Retinol and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture. This anti-aging seru

Paula's Choice Resist Intensive Wrinkle-Repair Retinol Serum Versus CeraVe Skin Renewing Retinol Serum

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

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Cyclopentasiloxane

Dimethiconol

Neopentyl Glycol Diheptanoate

Dicaprylyl Carbonate

Caprylic/Capric Triglyceride

Phenyl Trimethicone

Squalane

Bisabolol

Tetrahexyldecyl Ascorbate

Retinol

Tocotrienols

Tocopherol

Lecithin

Laminaria Ochroleuca Extract

Avena Sativa Kernel Extract

Elaeis Guineensis Oil

Stearyl Glycyrrhetinate

Hexylene Glycol

Caprylyl Glycol

Ethylhexylglycerin

Phenoxyethanol

Cyclopentasiloxane, Dimethiconol, Neopentyl Glycol Diheptanoate, Dicaprylyl Carbonate, Caprylic/Capric Triglyceride, Phenyl Trimethicone, Squalane, Bisabolol, Tetrahexyldecyl Ascorbate, Retinol, Tocotrienols, Tocopherol, Lecithin, Laminaria Ochroleuca Extract, Avena Sativa Kernel Extract, Elaeis Guineensis Oil, Stearyl Glycyrrhetinate, Hexylene Glycol, Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol

Water

Glycerin

Potassium Cetyl Phosphate

Hydrogenated Palm Glycerides

Polysorbate 20

PEG-40 Stearate

Hydroxyethylcellulose

Potassium Phosphate

Ceramide NP

Ceramide AP

Ceramide EOP

Carbomer

Niacinamide

Isoceteth-10

Dimethicone/Vinyl Dimethicone Crosspolymer

Triethanolamine

Cetearyl Alcohol

Behentrimonium Methosulfate

Cichorium Intybus Root Extract

Silica

Sodium Lauroyl Lactylate

Cholesterol

Alcohol

Hydroxyacetophenone

Citric Acid

Hydrolyzed Hyaluronic Acid

Pentylene Glycol

Xanthan Gum

Phytosphingosine

Butyrospermum Parkii Butter

Water, Glycerin, Caprylic/Capric Triglyceride, Potassium Cetyl Phosphate, Hydrogenated Palm Glycerides, Polysorbate 20, PEG-40 Stearate, Cyclopentasiloxane, Hydroxyethylcellulose, Potassium Phosphate, Ceramide NP, Ceramide AP, Ceramide EOP, Carbomer, Niacinamide, Isoceteth-10, Dimethicone/Vinyl Dimethicone Crosspolymer, Triethanolamine, Cetearyl Alcohol, Behentrimonium Methosulfate, Cichorium Intybus Root Extract, Lecithin, Retinol, Silica, Sodium Lauroyl Lactylate, Cholesterol, Phenoxyethanol, Tocopherol, Alcohol, Hydroxyacetophenone, Citric Acid, Hydrolyzed Hyaluronic Acid, Pentylene Glycol, Xanthan Gum, Phytosphingosine, Butyrospermum Parkii Butter, Ethylhexylglycerin

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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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.

Since D5 is volatile, it does its thing and then evaporates off the skin quickly.

The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics

There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.

Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.

The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

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.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

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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. 03Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.
  4. 04It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.
  5. 05The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.
  6. 06Trace 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).
  7. 07True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.
  8. 08Because it is derived from lauric acid, it may not be fungal acne safe.
  9. 09Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, …
  10. 10Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.
  11. 11Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.
  12. 12Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.
  13. 13It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.
  14. 14While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.
  15. 15If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.
  16. 16Tetrasodium EDTA is the salt formed from neutralizing ethylenediamine tetraacetic acid with sodium hydroxide. It is a chelating agent and used to prevent metal ions from binding to other ingredients. This helps keep the product and ingredients stable.
  17. 17Tetrasodium EDTA comes as a white solid and is soluble in water.
  18. 18Water. 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.
  19. 19So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
  20. 20You'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!
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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