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Candid 0.5% Retinol Treatment Versus Paula's Choice 1% Retinol Treatment

Candid 0.5% Retinol Treatment Versus Paula's Choice 1% Retinol Treatment This anti-aging serum is formulated around Niacinamide and Retinol to soften the look of wrinkles and refine skin texture. This anti-aging treatment is formulated around Retinol and Tetra

Candid 0.5% Retinol Treatment Versus Paula's Choice 1% Retinol Treatment

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

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Caprylic/Capric Triglyceride

Polysorbate 60

Niacinamide

Dimethicone

Methylpropanediol

Cetyl Alcohol

1,2-Hexanediol

Phenoxyethanol

Panthenol

BHT

Polysorbate 20

Retinol

Dimethicone/Vinyl Dimethicone Crosspolymer

Steareth-21

PEG-10 Dimethicone/Vinyl Dimethicone Crosspolymer

Cyclopentasiloxane

Polyacrylamide

Steareth-2

Isohexadecane

Elaeis Guineensis Oil

Carbomer

C13-14 Isoparaffin

Tromethamine

Palmitic Acid

Polyquaternium-51

Dioscorea Japonica Root Extract

Stearic Acid

Piper Methysticum Leaf/Root/Stem Extract

Tocopheryl Acetate

PEG-30 Dipolyhydroxystearate

Benzophenone-4

Ethylhexylglycerin

Hydroxyethylcellulose

Hydrogenated Lecithin

Glycosyl Trehalose

Beta-Glucan

Glyceryl Polymethacrylate

Panax Ginseng Berry Extract

Laureth-7

Centella Asiatica Extract

Hydrogenated Starch Hydrolysate

Disodium EDTA

Adenosine

Raffinose

Lecithin

Dipotassium Glycyrrhizate

BHA

Sodium Hyaluronate

Butylene Glycol

Myristic Acid

Folic Acid

Cholesterol

Ceramide NP

Disodium Phosphate

Biosaccharide Gum-1

Tocopherol

Sodium Phosphate

Palmitoyl Pentapeptide-4

Water, Glycerin, Caprylic/Capric Triglyceride, Polysorbate 60, Niacinamide, Dimethicone, Methylpropanediol, Cetyl Alcohol, 1,2-Hexanediol, Phenoxyethanol, Panthenol, BHT, Polysorbate 20, Retinol, Dimethicone/Vinyl Dimethicone Crosspolymer, Steareth-21, PEG-10 Dimethicone/Vinyl Dimethicone Crosspolymer, Cyclopentasiloxane, Polyacrylamide, Steareth-2, Isohexadecane, Elaeis Guineensis Oil, Carbomer, C13-14 Isoparaffin, Tromethamine, Palmitic Acid, Polyquaternium-51, Dioscorea Japonica Root Extract, Stearic Acid, Piper Methysticum Leaf/Root/Stem Extract, Tocopheryl Acetate, PEG-30 Dipolyhydroxystearate, Benzophenone-4, Ethylhexylglycerin, Hydroxyethylcellulose, Hydrogenated Lecithin, Glycosyl Trehalose, Beta-Glucan, Glyceryl Polymethacrylate, Panax Ginseng Berry Extract, Laureth-7, Centella Asiatica Extract, Hydrogenated Starch Hydrolysate, Disodium EDTA, Adenosine, Raffinose, Lecithin, Dipotassium Glycyrrhizate, BHA, Sodium Hyaluronate, Butylene Glycol, Myristic Acid, Folic Acid, Cholesterol, Ceramide NP, Disodium Phosphate, Biosaccharide Gum-1, Tocopherol, Sodium Phosphate, Palmitoyl Pentapeptide-4

Isononyl Isononanoate

Castor Isostearate Succinate

Glyceryl Stearate

C12-15 Alkyl Benzoate

Dimethicone Crosspolymer

PEG-33

Behenyl Alcohol

PEG-100 Stearate

Pentaerythrityl Tetraisostearate

Polymethylsilsesquioxane

Tetrahexyldecyl Ascorbate

Ceramide Ng

Palmitoyl Tetrapeptide-7

Palmitoyl Hexapeptide-12

Glycyrrhiza Glabra Root Extract

Avena Sativa Kernel Extract

Arctium Lappa Seed Oil

Salix Alba Extract

Glycine Soja Sterols

Allantoin

Hydrolyzed Soy Protein

Sorbitan Laurate

Acetyl Dipeptide-1 Cetyl Ester

Palmitoyl Tripeptide-1

Sodium Hydroxide

Tribehenin

Caprylyl Glycol

Pentylene Glycol

PEG-75 Shea Butter Glycerides

PPG-12/Smdi Copolymer

PEG-10 Phytosterol

PEG-8 Dimethicone

PEG-14

Magnesium Aluminum Silicate

Arachidyl Glucoside

Arachidyl Alcohol

Sclerotium Gum

Benzoic Acid

Water, Dimethicone, Glycerin, Butylene Glycol, Isononyl Isononanoate, Castor Isostearate Succinate, Glyceryl Stearate, C12-15 Alkyl Benzoate, Dimethicone Crosspolymer, PEG-33, Polysorbate 20, Behenyl Alcohol, PEG-100 Stearate, Pentaerythrityl Tetraisostearate, Polymethylsilsesquioxane, Tetrahexyldecyl Ascorbate, Retinol, Ceramide Ng, Palmitoyl Tetrapeptide-7, Palmitoyl Hexapeptide-12, Sodium Hyaluronate, Dipotassium Glycyrrhizate, Glycyrrhiza Glabra Root Extract, Avena Sativa Kernel Extract, Arctium Lappa Seed Oil, Salix Alba Extract, Glycine Soja Sterols, Lecithin, Allantoin, Tocopheryl Acetate, Hydrolyzed Soy Protein, Sorbitan Laurate, Acetyl Dipeptide-1 Cetyl Ester, Disodium EDTA, Hydroxyethylcellulose, Palmitoyl Tripeptide-1, Sodium Hydroxide, Tribehenin, Caprylyl Glycol, Ethylhexylglycerin, Pentylene Glycol, PEG-75 Shea Butter Glycerides, PPG-12/Smdi Copolymer, PEG-10 Phytosterol, PEG-8 Dimethicone, PEG-14, Magnesium Aluminum Silicate, Arachidyl Glucoside, Arachidyl Alcohol, Sclerotium Gum, Carbomer, Phenoxyethanol, Benzoic Acid

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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.

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

Dipotassium Glycyrrhizate comes from licorice root.

Extracts of licorice have demonstrated to have antibacterial, anti‐inflammatory, antiviral, antioxidant properties.

One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.

Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.

Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.

Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body that gives your features pigmentation.

Licorice root is native to Southern Europe and Asia. It has been used in traditional Chinese medicine to help with respiratory issues.

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

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.

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.

Hydroxyethylcellulose is used to improve the texture of products. It is created from a chemical reaction involving ethylene oxide and alkali-cellulose. Cellulose is a sugar found in plant cell walls and help give plants structure.

This ingredient helps stabilize products by preventing ingredients from separating. It can also help thicken the texture of a product.

This ingredient can also be found in pill medicines to help our bodies digest other ingredients.

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.

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.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.

Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

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.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

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!

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. 03Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).
  4. 04It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.
  5. 05This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.
  6. 06Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.
  7. 07The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.
  8. 08It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.
  9. 09Overall, avobenzone is a safe and regulated ingredient used in sunscreen for over 40 years.
  10. 10This ingredient is a silicone elastomer that works as a texture enhancer, adds a silky slip, and also helps absorb excess oil.
  11. 11Because it's a large macromolecule that's insoluble in water and chemically inert, it's not expected to penetrate or be absorbed into skin.
  12. 12Human patch tests with a facial lotion containing 1% of this ingredient found no sensitization.
  13. 13Ethylhexyl Salicylate (also called Octisalate or Octyl Salicylate) is an oil-soluble organic UV filter that's been used in sunscreen since the 1950's.
  14. 14It absorbs UVB light in the 280-320 nm range with a peak absorbance around 306 nm.
  15. 15You'll often see it paired with other UV filters to boost overall SPF because octisalate is a fairly week filter on its own.
  16. 16The reason you'll see it so often is because it can help solubilize and stabilize the trickier filters like oxybenzone and avobenzone.
  17. 17Unlike these filters, octisalate has pretty good photostability and doesn't create skin-damaging free radicals when exposed to sunlight.
  18. 18The fatty-alcohol part of the molecule also gives it a light, emollient feel so it doubles as a nice texture enhancer.
  19. 19Usage levels vary around the world:
  20. 20Safety-wise, this ingredient has a pretty reassuring track record. The EU's Scientific Committee on Consumer Products (SCCP) found very low skin penetration in human skin tests and negative results for irritation, phototoxicity, and photoallergy.
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, Jojoba Esters (Cleansing Beads), Caprylic/Capric Triglyceride (Skin-Replenishing), Glycerin (Skin Replenis…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side