Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Paula's Choice Clinical 0.3% Retinol + 2% Bakuchiol Treatment Versus Some By Mi Retinol Intense Reactivating Serum

Paula's Choice Clinical 0.3% Retinol + 2% Bakuchiol Treatment Versus Some By Mi Retinol Intense Reactivating Serum This anti-aging treatment is formulated around Bakuchiol and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture. Th

Paula's Choice Clinical 0.3% Retinol + 2% Bakuchiol Treatment Versus Some By Mi Retinol Intense Reactivating Serum

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

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

Dimethicone

Pentaerythrityl Tetraisostearate

Isononyl Isononanoate

Butylene Glycol

Bakuchiol

Arachidyl Alcohol

Glyceryl Polymethacrylate

Dimethicone Crosspolymer

Behenyl Alcohol

Glycerin

PEG-75 Shea Butter Glycerides

Glyceryl Stearate

C12-15 Alkyl Benzoate

Polysorbate 20

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 Root Extract

Salix Alba Bark Extract

Glycine Soja Sterols

Lecithin

Allantoin

Tocopheryl Acetate

Hydrolyzed Soy Protein

Palmitoyl Tripeptide-1

Sodium Hydroxide

Tribehenin

Caprylyl Glycol

Dipeptide-2

Polygonum Cuspidatum Root Extract

PEG-10 Phytosterol

PEG-8

Magnesium Aluminum Silicate

Arachidyl Glucoside

Chrysin

Pentylene Glycol

Sodium Acrylates Copolymer

Steareth-20

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Cetearyl Alcohol

Coco-Glucoside

Hesperidin Methyl Chalcone

N-Hydroxysuccinimide

Disodium EDTA

Phenoxyethanol

Benzoic Acid

Ethylhexylglycerin

Water, Dimethicone, Pentaerythrityl Tetraisostearate, Isononyl Isononanoate, Butylene Glycol, Bakuchiol, Arachidyl Alcohol, Glyceryl Polymethacrylate, Dimethicone Crosspolymer, Behenyl Alcohol, Glycerin, PEG-75 Shea Butter Glycerides, Glyceryl Stearate, C12-15 Alkyl Benzoate, Polysorbate 20, 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 Root Extract, Salix Alba Bark Extract, Glycine Soja Sterols, Lecithin, Allantoin, Tocopheryl Acetate, Hydrolyzed Soy Protein, Palmitoyl Tripeptide-1, Sodium Hydroxide, Tribehenin, Caprylyl Glycol, Dipeptide-2, Polygonum Cuspidatum Root Extract, PEG-10 Phytosterol, PEG-8, Magnesium Aluminum Silicate, Arachidyl Glucoside, Chrysin, Pentylene Glycol, Sodium Acrylates Copolymer, Steareth-20, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Cetearyl Alcohol, Coco-Glucoside, Hesperidin Methyl Chalcone, N-Hydroxysuccinimide, Disodium EDTA, Phenoxyethanol, Benzoic Acid, Ethylhexylglycerin

Cyclohexasiloxane

Dicaprylyl Carbonate

Methylpropanediol

1,2-Hexanediol

Niacinamide

Hydrogenated Poly(C6-14 Olefin)

Panthenol

Piper Methysticum Leaf/Root/Stem Extract

Centella Asiatica Extract

Panax Ginseng Berry Extract

Ficus Carica Fruit Extract

Centella Asiatica Leaf Extract

Centella Asiatica Root Extract

Melaleuca Alternifolia Leaf Extract

Artemisia Capillaris Extract

Eclipta Prostrata Extract

Melia Azadirachta Leaf Extract

Elaeis Guineensis Oil

Hydrogenated Lecithin

Palmitic Acid

Sodium Polyacrylate

Stearic Acid

Xanthan Gum

Retinol 0.1%

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Adenosine

Tromethamine

Polyquaternium-51

Beta-Glucan

Cetyl Alcohol

BHT

Collagen

Myristic Acid

BHA

Leuconostoc/Radish Root Ferment Filtrate

Tocopherol

Bifida Ferment Lysate

Ceramide NP

Saccharomyces Ferment

Retinal

Asiaticoside

Madecassoside

Propylene Glycol

Polyglyceryl-10 Oleate

Glycolipids

Glycine Soja Peptide

Resveratrol

Sucrose Distearate

Asiatic Acid

Madecassic Acid

Moringa Oleifera Seed Oil

PEG-100 Stearate

Parfum

Water, Cyclohexasiloxane, Dicaprylyl Carbonate, Glycerin, Methylpropanediol, 1,2-Hexanediol, Niacinamide, Hydrogenated Poly(C6-14 Olefin), Panthenol, Tocopheryl Acetate, Piper Methysticum Leaf/Root/Stem Extract, Centella Asiatica Extract, Panax Ginseng Berry Extract, Glycyrrhiza Glabra Root Extract, Ficus Carica Fruit Extract, Centella Asiatica Leaf Extract, Centella Asiatica Root Extract, Melaleuca Alternifolia Leaf Extract, Artemisia Capillaris Extract, Eclipta Prostrata Extract, Melia Azadirachta Leaf Extract, Elaeis Guineensis Oil, Hydrogenated Lecithin, Glyceryl Stearate, Bakuchiol, Palmitic Acid, Sodium Polyacrylate, Stearic Acid, Xanthan Gum, Retinol 0.1%, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Butylene Glycol, Dipotassium Glycyrrhizate, Adenosine, Tromethamine, Polyquaternium-51, Beta-Glucan, Cetyl Alcohol, BHT, Collagen, Myristic Acid, BHA, Leuconostoc/Radish Root Ferment Filtrate, Tocopherol, Bifida Ferment Lysate, Ceramide NP, Saccharomyces Ferment, Retinal, Asiaticoside, Glyceryl Polymethacrylate, Madecassoside, Propylene Glycol, Polyglyceryl-10 Oleate, Glycolipids, Glycine Soja Peptide, Resveratrol, Sucrose Distearate, Asiatic Acid, Madecassic Acid, Palmitoyl Tripeptide-1, Moringa Oleifera Seed Oil, PEG-100 Stearate, Polysorbate 20, Parfum, Ethylhexylglycerin

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.

Bakuchiol is a plant-derived antioxidant from the seeds of the Psoralea corylifolia plant. It has antimicrobial, emollient, skin conditioning, and antioxidant properties.

You'll likely see it called a "retinol replacement" but the two are technically not related. This is because bakuchiol is able to flip many of the same switches in your skin cells to tell them to:

1) produce more collagen (type I, III, and IV) 2) activate the same genes retinoids do

Unlike retinoids, this ingredient will not increase photosensitivity and is safe to use during pregnancy (but please still check in with your doctor!).

The flagship clinical trial from Dhaliwal et al. 2019 found 0.5% bakuchiol (twice daily) and 0.5% retinol (once daily) reduced wrinkles and hyperpigmentation equally, but bakuchiol had significantly less irritation.

Systematic reviews also back this up:

Bakuchiol is comparable to retinol for photoaging but with better tolerability. It also has mild antibacterial properties against Cutibacterium acnes and antifungal activity in vitro against Candida and dermatophytes.

The reason bakuchiol works well is due to its structure; it is a meroterpene phenol, or a hybrid molecule. The phenol half acts as an antioxidant while the terpene half is fat-loving. This helps the molecule slip through the skin barrier.

This ingredient is usually used between 0.5-2%. Only one case of contact dermatitis has ever been reported for this ingredient.

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.

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.

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.

This is a synthetic polymer made by combining glycerin with polymethacrylic acid.

It is a non-drying, non-greasy moisturizer that helps enhance the feel and slip of formulations, helps stabilize emulsions, creates a film, and controls viscosity.

As a film former, it creates a light and flexible layer on the skin's surface. This helps lock in moisture without feeling heavy.

It's typically used at concentrations up to 1.9% in leave-on products. CIR has concluded that these ingredients are safe in cosmetics at current use levels.

Due to its large molecule size, it doesn't readily penetrate into skin and mostly just sits on the surface. A large UK-based patch test study of over 1,300 patients found that sensitization to related acrylate copolymers is rare.

Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.

Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

Glycyrrhiza Glabra Root Extract is an extract of the roots of Licorice. It has been found to have several benefits such as skin hydrating, conditioning, and soothing.

Palmitoyl Tripeptide-1 (aka Pal-GHK) is a synthetic signal peptide made of three amino acids attached to palmitic acid.

That fatty acid attachment is the key: it boosts the peptide's ability to penetrate the skin barrier. This puts it closer to the dermal cells where it can actually make a difference.

Once there, it acts as a matrikine, a signaling peptide that prompts fibroblasts to produce more collagen, fibronectin, and hyaluronic acid.

In vitro studies show it can boost collagen production in skin cells even when UV-damaged skin samples were treated with it at a tiny concentration (it almost fully restored dermal collagen at 5ppm). It achieved this at 100x lower concentration than retinoic acid, which needed 500 ppm to do the same thing.

Human clinical data is promising, but modest:

A study of 23 female volunteers found a small but statistically significant increase (~4%) in skin thickness after treatment at 4 ppm.

A separate small trial of 15 women showed statistically significant reductions in wrinkle length, depth, and skin roughness after applying it twice daily for four weeks.

You'll likely see Pal-GHK paired with Palmitoyl Tetrapeptide-7 as part of the Matrixyl 3000 complex.

Fungal acne note: Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

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.

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 Side-by-side

  1. 01Water
  2. 02Sodium Cocoyl Glutamate
  3. 03Glycerin
  4. 04Caprylic/Capric Triglyceride
  5. 05Cocamidopropyl Betaine
  6. 06Sodium Laurylglucosides Hydroxypropylsulfonate
  7. 07Cellulose Gum
  8. 08Coco-Caprylate/Caprate
  9. 09Hydroxyacetophenone
  10. 10Inulin
  11. 11Xanthan Gum
  12. 12Ethylhexylglycerin
  13. 13Sodium Phytate
  14. 14Cellulose
  15. 15Fructose
  16. 16Glucose
  17. 17Phenoxyethanol
  18. 18Water, Sodium Cocoyl Glutamate, Glycerin, Caprylic/Capric Triglyceride, Cocamidopropyl Betaine, Sodium Laurylglucosides Hydroxypropylsulfonate, Cellulose Gum, Coco-Caprylate/Caprate, Hydroxyacetophenone, Inulin, Xanthan Gum, Ethylhexylglycerin, Sodi…
  19. 19Cocamidopropyl Hydroxysultaine
  20. 20Sodium Lauroyl Sarcosinate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side