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Skin science article

Kiehl's Super Multi-Corrective Anti-Aging Eye Cream Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide

Kiehl's Super Multi-Corrective Anti-Aging Eye Cream Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide This anti-aging eye moisturizer is formulated around Niacinamide and Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and r

Kiehl's Super Multi-Corrective Anti-Aging Eye Cream Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide

This anti-aging eye moisturizer is formulated around Niacinamide and Palmitoyl Tetrapeptide-7 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

Dimethicone

Glycerin

Hydroxypropyl Tetrahydropyrantriol

Niacinamide

Alcohol Denat.

Propylene Glycol

Silica

Propanediol

Polysilicone-11

PEG-10 Dimethicone

Di-C12-13 Alkyl Malate

Vaccinium Myrtillus Seed Oil

Dimethicone/PEG-10/15 Crosspolymer

Hydroxyethylpiperazine Ethane Sulfonic Acid

Bis-PEG/PPG-16/16 PEG/PPG-16/16 Dimethicone

Potassium Cetyl Phosphate

Carbomer

Ceteareth-20

Caffeine

Sodium Citrate

Sodium Hyaluronate

Sodium Hydroxide

Sodium Lactate

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Adenosine

Ammonium Polyacryloyldimethyl Taurate

Boron Nitride

Dipropylene Glycol

Caprylic/Capric Triglyceride

Caprylyl Glycol

Trisodium Ethylenediamine Disuccinate

Polysorbate 20

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Butylene Glycol

Tocopherol

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Chlorhexidine Digluconate

Chlorphenesin

Water, Dimethicone, Glycerin, Hydroxypropyl Tetrahydropyrantriol, Niacinamide, Alcohol Denat., Propylene Glycol, Silica, Propanediol, Polysilicone-11, PEG-10 Dimethicone, Di-C12-13 Alkyl Malate, Vaccinium Myrtillus Seed Oil, Dimethicone/PEG-10/15 Crosspolymer, Hydroxyethylpiperazine Ethane Sulfonic Acid, Bis-PEG/PPG-16/16 PEG/PPG-16/16 Dimethicone, Potassium Cetyl Phosphate, Carbomer, Ceteareth-20, Caffeine, Sodium Citrate, Sodium Hyaluronate, Sodium Hydroxide, Sodium Lactate, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1, Adenosine, Ammonium Polyacryloyldimethyl Taurate, Boron Nitride, Dipropylene Glycol, Caprylic/Capric Triglyceride, Caprylyl Glycol, Trisodium Ethylenediamine Disuccinate, Polysorbate 20, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Butylene Glycol, Tocopherol, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Chlorhexidine Digluconate, Chlorphenesin

Pentylene Glycol

Cetyl Alcohol

Isohexadecane

Isononyl Isononanoate

Diisopropyl Sebacate

2-Oleamido-1,3-Octadecanediol

4-T-Butylcyclohexanol

Acetyl Dipeptide-1 Cetyl Ester

Ceramide NP

Hydroxypalmitoyl Sphinganine

Lauroyl Lysine

Octyldodecanol

Sodium Chloride

Retinol

Dicaprylyl Ether

Behenyl Alcohol

Cetearyl Alcohol

Cetearyl Glucoside

Glycine Soja Oil

Helianthus Annuus Seed Oil

Hydroxyethylcellulose

Lecithin

Phenethyl Alcohol

Poloxamer 188

Polycaprolactone

Sorbitan Laurate

Steareth-100

CI 40800

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.

Ammonium Polyacryloyldimethyl Taurate is a polymer made from ammonium salts. It works as a thickener, emulsifier, and texture enhancer that gives gel-creams a silky, lightweight feel.

This ingredient is versatile and low-maintenance so manufacturers love working with it.

Typical usage levels in cosmetics are usually low and in the range of 0.015 - 2.3%.

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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

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.

Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol.

Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria.

Chlorphenesin is soluble in both water and glycerin.

Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin.

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.

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate (long name, huh?) is a synthetic antioxidant.

It is used to help stabilize other antioxidants or prevent the color from changing in a product.

As an antioxidant, it helps fight free-radical molecules. Free-radical molecules are capable of damaging our cells and other genetic material. Thus, antioxidants may reduce the signs of aging.

This ingredient is oil-soluble.

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.

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.

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.

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

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. 02Glycerin
  3. 03Butylene Glycol
  4. 04Pentylene Glycol
  5. 05Niacinamide
  6. 06Cetyl Alcohol
  7. 07Isohexadecane
  8. 08Isononyl Isononanoate
  9. 09Diisopropyl Sebacate
  10. 102-Oleamido-1,3-Octadecanediol
  11. 114-T-Butylcyclohexanol
  12. 12Acetyl Dipeptide-1 Cetyl Ester
  13. 13Adenosine
  14. 14Ceramide NP
  15. 15Hydroxypalmitoyl Sphinganine
  16. 16Lauroyl Lysine
  17. 17Octyldodecanol
  18. 18Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate
  19. 19Sodium Chloride
  20. 20Sodium Hyaluronate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side