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Allies of Skin Peptides & Omegas Firming Eye Cream Versus Medik8 Crystal Retinal Ceramide Eye

Allies of Skin Peptides & Omegas Firming Eye Cream Versus Medik8 Crystal Retinal Ceramide Eye This anti-aging eye moisturizer is formulated around Squalane and Bakuchiol to soften the look of wrinkles and strengthen the skin barrier. This anti-aging eye moistu

Allies of Skin Peptides & Omegas Firming Eye Cream Versus Medik8 Crystal Retinal Ceramide Eye

This anti-aging eye moisturizer is formulated around Squalane and Bakuchiol to soften the look of wrinkles and strengthen the skin barrier.

This anti-aging eye moisturizer is formulated around Retinal and Ceramide NP to soften the look of wrinkles and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Tribehenin

Caprylic/Capric Triglyceride

Isodecyl Neopentanoate

Glyceryl Stearate

Propanediol

Squalane

Acrylamide/Sodium Acryloyldimethyltaurate Copolymer

Leuconostoc/Radish Root Ferment Filtrate

Caprylyl Glycol

Bakuchiol

Sodium Ascorbyl Phosphate

Ceramide NP

Rosa Canina Seed Oil

Adansonia Digitata Seed Oil

Argania Spinosa Kernel Oil

Glycyrrhiza Glabra Root Extract

Pfaffia Paniculata Root Extract

Ptychopetalum Olacoides Bark/Stem Extract

Calanthe Discolor Extract

Lilium Candidum Flower Extract

Ubiquinone

Superoxide Dismutase

Ergothioneine

Tocopheryl Acetate

Bisabolol

Allantoin

Biotin

Hesperidin Methyl Chalcone

Methylglucoside Phosphate

Copper Lysinate/Prolinate

Palmitoyl Tetrapeptide-7

Chrysin

Gluconolactone

Dipeptide-2

Palmitoyl Tripeptide-1

N-Prolyl Palmitoyl Tripeptide-56 Acetate

Calcium Gluconate

N-Hydroxysuccinimide

Caprylyl/Capryl Glucoside

Citric Acid

Glyceryl Polyacrylate

Isohexadecane

Pentylene Glycol

Polysorbate 80

Sodium Citrate

Sodium Gluconate

Sodium Hydroxide

Sorbitan Oleate

Steareth-20

Xanthan Gum

Benzyl Alcohol

Chlorhexidine Digluconate

Sodium Benzoate

Potassium Sorbate

Phenoxyethanol

Water, Glycerin, Tribehenin, Caprylic/Capric Triglyceride, Isodecyl Neopentanoate, Glyceryl Stearate, Propanediol, Squalane, Acrylamide/Sodium Acryloyldimethyltaurate Copolymer, Leuconostoc/Radish Root Ferment Filtrate, Caprylyl Glycol, Bakuchiol, Sodium Ascorbyl Phosphate, Ceramide NP, Rosa Canina Seed Oil, Adansonia Digitata Seed Oil, Argania Spinosa Kernel Oil, Glycyrrhiza Glabra Root Extract, Pfaffia Paniculata Root Extract, Ptychopetalum Olacoides Bark/Stem Extract, Calanthe Discolor Extract, Lilium Candidum Flower Extract, Ubiquinone, Superoxide Dismutase, Ergothioneine, Tocopheryl Acetate, Bisabolol, Allantoin, Biotin, Hesperidin Methyl Chalcone, Methylglucoside Phosphate, Copper Lysinate/Prolinate, Palmitoyl Tetrapeptide-7, Chrysin, Gluconolactone, Dipeptide-2, Palmitoyl Tripeptide-1, N-Prolyl Palmitoyl Tripeptide-56 Acetate, Calcium Gluconate, N-Hydroxysuccinimide, Caprylyl/Capryl Glucoside, Citric Acid, Glyceryl Polyacrylate, Isohexadecane, Pentylene Glycol, Polysorbate 80, Sodium Citrate, Sodium Gluconate, Sodium Hydroxide, Sorbitan Oleate, Steareth-20, Xanthan Gum, Benzyl Alcohol, Chlorhexidine Digluconate, Sodium Benzoate, Potassium Sorbate, Phenoxyethanol

Butyrospermum Parkii Butter

Arachidyl Alcohol

Cetearyl Isononanoate

Isododecane

Ethylhexyl Palmitate

Behenyl Alcohol

Cetearyl Alcohol

Microcrystalline Cellulose

PPG-12/Smdi Copolymer

Phytosterols

Arachidyl Glucoside

Dimethicone

Sodium Acrylates Copolymer

Tocopherol

Linoleic Acid

Cyclodextrin

Hydroxyacetophenone

Sodium Stearoyl Glutamate

Helianthus Annuus Seed Oil

Lecithin

Sodium Hyaluronate

Retinal

Pandanus Conoideus Fruit Oil

Daucus Carota Sativa Seed Oil

Lonicera Japonica Flower Extract

Lonicera Caprifolium Flower Extract

Sodium Polyaspartate

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Disodium EDTA

Rubus Chamaemorus Seed Oil

Ethylhexylglycerin

Cellulose

BHT

Trihydroxystearin

Water, Caprylic/Capric Triglyceride, Butyrospermum Parkii Butter, Propanediol, Arachidyl Alcohol, Cetearyl Isononanoate, Glycerin, Isododecane, Squalane, Ethylhexyl Palmitate, Behenyl Alcohol, Cetearyl Alcohol, Glyceryl Stearate, Microcrystalline Cellulose, PPG-12/Smdi Copolymer, Tocopheryl Acetate, Phytosterols, Phenoxyethanol, Arachidyl Glucoside, Dimethicone, Sodium Acrylates Copolymer, Tocopherol, Linoleic Acid, Ceramide NP, Cyclodextrin, Bisabolol, Hydroxyacetophenone, Sodium Stearoyl Glutamate, Helianthus Annuus Seed Oil, Lecithin, Sodium Hyaluronate, Retinal, Pandanus Conoideus Fruit Oil, Daucus Carota Sativa Seed Oil, Lonicera Japonica Flower Extract, Lonicera Caprifolium Flower Extract, Sodium Polyaspartate, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Disodium EDTA, Rubus Chamaemorus Seed Oil, Xanthan Gum, Ethylhexylglycerin, Cellulose, BHT, Sodium Hydroxide, Pentylene Glycol, Trihydroxystearin

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.

Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient.

It's primary claim to fame is soothing and research shows topically applied bisabolol can quiet the chemical messengers that cause your skin to become inflamed, helping to sooth any irritation.

A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin.

In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.

You'll likely see use concentrations quite low, usually 0.1-0.2%.

Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

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.

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.

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.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

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.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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