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Some By Mi Retinol Intense Reactivating Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide

Some By Mi Retinol Intense Reactivating Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide This anti-aging serum is formulated around Retinol and Bakuchiol to soften the look of wrinkles and refine skin texture. This anti-aging

Some By Mi Retinol Intense Reactivating Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide

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

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Pentylene Glycol

Isohexadecane

Isononyl Isononanoate

Diisopropyl Sebacate

2-Oleamido-1,3-Octadecanediol

4-T-Butylcyclohexanol

Acetyl Dipeptide-1 Cetyl Ester

Hydroxypalmitoyl Sphinganine

Lauroyl Lysine

Octyldodecanol

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Sodium Chloride

Sodium Hyaluronate

Sodium Hydroxide

Trisodium Ethylenediamine Disuccinate

Retinol

Dicaprylyl Ether

Ammonium Polyacryloyldimethyl Taurate

Behenyl Alcohol

Caprylyl Glycol

Carbomer

Cetearyl Alcohol

Cetearyl Glucoside

Glycine Soja Oil

Helianthus Annuus Seed Oil

Hydroxyethylcellulose

Lecithin

Phenethyl Alcohol

Poloxamer 188

Polycaprolactone

Sorbitan Laurate

Steareth-100

CI 40800

Chlorphenesin

Phenoxyethanol

Water, Glycerin, Butylene Glycol, Pentylene Glycol, Niacinamide, Cetyl Alcohol, Isohexadecane, Isononyl Isononanoate, Diisopropyl Sebacate, 2-Oleamido-1,3-Octadecanediol, 4-T-Butylcyclohexanol, Acetyl Dipeptide-1 Cetyl Ester, Adenosine, Ceramide NP, Hydroxypalmitoyl Sphinganine, Lauroyl Lysine, Octyldodecanol, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Chloride, Sodium Hyaluronate, Sodium Hydroxide, Trisodium Ethylenediamine Disuccinate, Retinol, Tocopherol, Dicaprylyl Ether, Ammonium Polyacryloyldimethyl Taurate, Behenyl Alcohol, Caprylyl Glycol, Carbomer, Cetearyl Alcohol, Cetearyl Glucoside, Glycine Soja Oil, Helianthus Annuus Seed Oil, Hydroxyethylcellulose, Lecithin, Phenethyl Alcohol, Poloxamer 188, Polycaprolactone, Sorbitan Laurate, Steareth-100, CI 40800, Chlorphenesin, Phenoxyethanol

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.

Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.

The way it works is fairly well mapped out:

Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down on their own as skin ages, so Adenosine helps give them a little nudge to keep going.

The clinical backing is pretty solid too.

A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at 2 months.

A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.

On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.

This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.

Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.

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.

Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.

Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.

This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.

A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.

Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.

Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.

Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.

Cetyl Alcohol is a fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product.

Its main roles are:

Though it has "alcohol" in the name, it is not related to denatured alcohol or ethyl alcohol.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

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.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

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.

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. 03Carbomer 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.
  4. 04Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  5. 05It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  6. 06Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  7. 07A 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.
  8. 08Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  9. 09Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
  10. 10It plays several roles in a formula:
  11. 11Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
  12. 12Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  13. 13However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  14. 14Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.
  15. 15Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.
  16. 16Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.
  17. 17This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.
  18. 18A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.
  19. 19Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  20. 20Topically, glycerin does several things at once:
Source · skinsort.com
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Product index

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Comparison edit

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