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No7 Restore & Renew Multi Action Face & Neck Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide

No7 Restore & Renew Multi Action Face & Neck Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide This anti-aging serum is formulated around Gluconolactone and 3-O-Ethyl Ascorbic Acid to soften the look of wrinkles and strengthen

No7 Restore & Renew Multi Action Face & Neck Serum Versus Kiehl's Micro-Dose Anti-Aging Retinol Serum with Ceramides and Peptide

This anti-aging serum is formulated around Gluconolactone and 3-O-Ethyl Ascorbic Acid to soften the look of wrinkles and strengthen the skin barrier.

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

Butylene Glycol

Aluminum Starch Octenylsuccinate

Isononyl Isononanoate

Gluconolactone

Dimethicone Crosspolymer

Cetearyl Alcohol

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Phenoxyethanol

3-O-Ethyl Ascorbic Acid

Pentylene Glycol

Polysorbate 20

Potassium Hydroxide

Xanthan Gum

Dimethiconol

Hibiscus Abelmoschus Extract

Parfum

Sodium Hyaluronate

Retinyl Palmitate

Caprylyl Glycol

Propylene Glycol

Sorbitan Laurate

Tocopheryl Acetate

Hydrolyzed Rice Protein

Ethylhexylglycerin

Carbomer

Sodium Lauroyl Lactylate

3-Aminopropane Sulfonic Acid

Calcium Hydroxymethionine

Phyllanthus Emblica Fruit Extract

Dipropylene Glycol

Hydroxyethylcellulose

Tetrasodium EDTA

T-Butyl Alcohol

Panax Ginseng Root Extract

Sophora Angustifolia Root Extract

Hydroxypropyl Cyclodextrin

Acetyl Dipeptide-1 Cetyl Ester

Ceramide NP

Morus Alba Leaf Extract

Sodium Benzoate

Ceramide AP

Phytosphingosine

Cholesterol

Tocopherol

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Ceramide EOP

Water, Dimethicone, Glycerin, Butylene Glycol, Aluminum Starch Octenylsuccinate, Isononyl Isononanoate, Gluconolactone, Dimethicone Crosspolymer, Cetearyl Alcohol, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Phenoxyethanol, 3-O-Ethyl Ascorbic Acid, Pentylene Glycol, Polysorbate 20, Potassium Hydroxide, Xanthan Gum, Dimethiconol, Hibiscus Abelmoschus Extract, Parfum, Sodium Hyaluronate, Retinyl Palmitate, Caprylyl Glycol, Propylene Glycol, Sorbitan Laurate, Tocopheryl Acetate, Hydrolyzed Rice Protein, Ethylhexylglycerin, Carbomer, Sodium Lauroyl Lactylate, 3-Aminopropane Sulfonic Acid, Calcium Hydroxymethionine, Phyllanthus Emblica Fruit Extract, Dipropylene Glycol, Hydroxyethylcellulose, Tetrasodium EDTA, T-Butyl Alcohol, Panax Ginseng Root Extract, Sophora Angustifolia Root Extract, Hydroxypropyl Cyclodextrin, Acetyl Dipeptide-1 Cetyl Ester, Ceramide NP, Morus Alba Leaf Extract, Sodium Benzoate, Ceramide AP, Phytosphingosine, Cholesterol, Tocopherol, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Ceramide EOP

Niacinamide

Cetyl Alcohol

Isohexadecane

Diisopropyl Sebacate

2-Oleamido-1,3-Octadecanediol

4-T-Butylcyclohexanol

Adenosine

Hydroxypalmitoyl Sphinganine

Lauroyl Lysine

Octyldodecanol

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Sodium Chloride

Sodium Hydroxide

Trisodium Ethylenediamine Disuccinate

Retinol

Dicaprylyl Ether

Ammonium Polyacryloyldimethyl Taurate

Behenyl Alcohol

Cetearyl Glucoside

Glycine Soja Oil

Helianthus Annuus Seed Oil

Lecithin

Phenethyl Alcohol

Poloxamer 188

Polycaprolactone

Steareth-100

CI 40800

Chlorphenesin

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

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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.

Acetyl Dipeptide-1 Cetyl Ester is a peptide composed of amino acids arginine and tyrosine.

This peptide is considered a neurotransmitter peptide, meaning it has pain-relieving and relaxing properties. It has the ability to calm skin irritation from external factors such as chemical stinging or heat.

Neurotransmitter peptides are also often called "botox in a bottle". This is because these peptides have the ability to relax the muscles.

Though relaxing the muscles can prevent expression lines (as we have seen in botox), the studies do not show these peptides to be a botox replacement. The effects of this muscle relaxation is also short-term, as opposed to longer-term results from botox.

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.

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.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite 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.

It plays several roles in a formula:

Typical 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.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl 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.

Here'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.

Remember 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.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

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.

Isononyl Isononanoate is a synthetic skin-conditioner and texture enhancer. It is created from nonanoic acid, a fatty acid found in cocoa and lavender oil.

As an emollient, Isononyl Isononanoate helps keep your skin soft and smooth. This is because emollients create a barrier on the skin to trap moisture in.

Isononyl Isononanoate helps give products a velvet feel and improves spreadability.

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

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.

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.

Sorbitan Laurate is created from lauric acid and derivatives from sorbitol. It is an emulsifier.

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.

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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. 03Adenosine 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.
  4. 04The way it works is fairly well mapped out:
  5. 05Your 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 o…
  6. 06The clinical backing is pretty solid too.
  7. 07A 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…
  8. 08A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.
  9. 09On 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.
  10. 10This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.
  11. 11Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.
  12. 12Ammonium 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.
  13. 13This ingredient is versatile and low-maintenance so manufacturers love working with it.
  14. 14Typical usage levels in cosmetics are usually low and in the range of 0.015 - 2.3%.
  15. 15Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  16. 16Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  17. 17Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  18. 18Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  19. 19Topically, glycerin does several things at once:
  20. 20Your 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.
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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