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The INKEY List Brighten-I Eye Cream Versus Peter Thomas Roth Instant FIRMx Eye™

The INKEY List Brighten-I Eye Cream Versus Peter Thomas Roth Instant FIRMx Eye™ This eye moisturizer is formulated around Punica Granatum Seed Oil to hydrate skin. This anti-aging eye moisturizer is formulated around Palmitoyl Tetrapeptide-7 and Dipeptide-2 to

The INKEY List Brighten-I Eye Cream Versus Peter Thomas Roth Instant FIRMx Eye™

This eye moisturizer is formulated around Punica Granatum Seed Oil to hydrate skin.

This anti-aging eye moisturizer is formulated around Palmitoyl Tetrapeptide-7 and Dipeptide-2 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Dimethicone

Coco-Caprylate/Caprate

Glycerin

Caprylic/Capric Triglyceride

Glyceryl Stearate

Candelilla/Jojoba/Rice Bran Polyglyceryl-3 Esters

Punica Granatum Seed Oil

Ethylhexyl Palmitate

Mica

Phenoxyethanol

Cetearyl Alcohol

Sodium Stearoyl Lactylate

Benzyl Alcohol

Polysilicone-11

Hydroxyacetophenone

Sodium Stearoyl Glutamate

Tocopheryl Acetate

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Sodium Gluconate

Ethylhexylglycerin

Silica

Dehydroacetic Acid

Diglucosyl Gallic Acid

Sodium Hydroxide

Trihydroxystearin

Tin Oxide

Sodium Hyaluronate

Glucomannan

CI 77891

Water, Dimethicone, Coco-Caprylate/Caprate, Glycerin, Caprylic/Capric Triglyceride, Glyceryl Stearate, Candelilla/Jojoba/Rice Bran Polyglyceryl-3 Esters, Punica Granatum Seed Oil, Ethylhexyl Palmitate, Mica, Phenoxyethanol, Cetearyl Alcohol, Sodium Stearoyl Lactylate, Benzyl Alcohol, Polysilicone-11, Hydroxyacetophenone, Sodium Stearoyl Glutamate, Tocopheryl Acetate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Gluconate, Ethylhexylglycerin, Silica, Dehydroacetic Acid, Diglucosyl Gallic Acid, Sodium Hydroxide, Trihydroxystearin, Tin Oxide, Sodium Hyaluronate, Glucomannan, CI 77891

Butylene Glycol

Sodium Silicate

Magnesium Aluminum Silicate

Sodium Magnesium Fluorosilicate

Palmitoyl Tetrapeptide-7

Dipeptide-2

Ascorbic Acid

Hesperidin Methyl Chalcone

Retinyl Palmitate

Panthenol

Foeniculum Vulgare Seed Extract

Medicago Sativa Seed Extract

Carrageenan

Argania Spinosa Kernel Extract

PEG-8 Dimethicone

Octyldodecanol

Symphytum Officinale Leaf Extract

Sodium Propoxyhydroxypropyl Thiosulfate Silica

BHT

Disodium EDTA

Hydrolyzed Lupine Protein

Steareth-20

Sodium Cocoyl Glutamate

Carbomer

Chlorhexidine Digluconate

Potassium Sorbate

Citric Acid

Sodium Citrate

Sodium Benzoate

Water, Glycerin, Butylene Glycol, Sodium Silicate, Magnesium Aluminum Silicate, Sodium Magnesium Fluorosilicate, Palmitoyl Tetrapeptide-7, Dipeptide-2, Ascorbic Acid, Tocopheryl Acetate, Hesperidin Methyl Chalcone, Retinyl Palmitate, Panthenol, Foeniculum Vulgare Seed Extract, Medicago Sativa Seed Extract, Carrageenan, Argania Spinosa Kernel Extract, PEG-8 Dimethicone, Silica, Octyldodecanol, Symphytum Officinale Leaf Extract, Sodium Propoxyhydroxypropyl Thiosulfate Silica, BHT, Disodium EDTA, Hydrolyzed Lupine Protein, Steareth-20, Sodium Cocoyl Glutamate, Carbomer, Chlorhexidine Digluconate, Ethylhexylglycerin, Potassium Sorbate, Citric Acid, Sodium Citrate, Sodium Benzoate, 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.

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.

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.

Silica, also known as silicon dioxide, is a naturally occurring mineral. It is used as a fine, spherical, and porous powder in cosmetics.

Though it has exfoliant properties, the function of silica varies depending on the product.

The unique structure of silica enhances the spreadability and adds smoothness, making it a great texture enhancer.

It is also used as an active carrier, emulsifier, and mattifier due to its ability to absorb excess oil.

In some products, tiny microneedles called spicules are made from silica or hydrolyzed sponge. When you rub them in, they lightly polish away dead skin layers and enhance the penetration of active ingredients.

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 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. 03Aloe Barbadensis Leaf Juice is the filtered, stabilized liquid pressed from the inner gel of the aloe vera leaf.
  4. 04In cosmetics, it shows up as either soothing active or a water-replacement base. It is roughly 98-99% water and the last 1-2% is an interesting mix of polysaccharides, amino acids, vitamins, minerals, and enzymes.
  5. 05The polysaccharides do most of the work: they bind water at the skin surface for a light, non-greasy hydration boost. And one of the polysaccharides, glycomannan, is linked to fibroblast stimulation + collagen synthesis. This is also why aloe has su…
  6. 06This ingredient is also calming with anti-inflammatory and mild antimicrobial activity, making it a great pick for sensitive, irritated, or post-sun skin.
  7. 07Realistic expectations matter though; the solid evidence is mostly limited to hydration, soothing, and wound support. Deeper claims about anti-aging or sun protection are not well backed, and science reviews note it does not prevent radiation-induce…
  8. 08Because it plays well with almost everything, it's commonly used as a base alongside other actives like niacinamide or vitamin C.
  9. 09Typical usage concentrations range from 0.5% (where hydration benefits already show up) all the way to 90%+ (where it replaces water as the main base).
  10. 10The safety for this ingredient is well-establish as well. Overall, this is a great supporting ingredient for those who want a boost in hydration.
  11. 11Carthamus Tinctorius Seed Oil comes from the seeds of the safflower plant. It is a skin conditioning agent that helps soften skin and keep it hydrated.
  12. 12This seed oil has an unusual fatty acid profile: it is one of the highest linoleic acid plant oils out there (~55-77%). It also has low amounts of oleic acid, and this high-linoleic/low-oleic ratio gets people excited.
  13. 13Linoleic acid helps maintain skin barrier integrity and is a building block for the ceramides in your stratum corneum. Notably, people with acne tend to have lower linoleic acid in their skin lipids as well (and this gets worse as acne gets more severe).
  14. 14Overall, it's a lightweight, fast-absorbing oil that has a long safety track record. Lab testing has found it to be non-irritating for skin or eyes.
  15. 15The Malassezia yeast can metabolize the fatty acids in this oil to grow; therefore this ingredient may not be fungal acne safe.
  16. 16Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  17. 17Topically, glycerin does several things at once:
  18. 18Your 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.
  19. 19Aquaporin-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.
  20. 20This 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.
Source · skinsort.com
02

Product index

Related product references

Product

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Source: incidecoder.comView reference →
03

Comparison edit

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