Peptide Skincare & BeautySkin science and ingredient guides

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Catrice Caffeine Kick Under Eye Serum Versus The INKEY List Caffeine Eye Cream

Catrice Caffeine Kick Under Eye Serum Versus The INKEY List Caffeine Eye Cream This anti-aging eye moisturizer is formulated around Caffeine and Niacinamide to soften the look of wrinkles and brighten dull-looking skin. This anti-aging eye moisturizer is formu

Catrice Caffeine Kick Under Eye Serum Versus The INKEY List Caffeine Eye Cream

This anti-aging eye moisturizer is formulated around Caffeine and Niacinamide to soften the look of wrinkles and brighten dull-looking skin.

This anti-aging eye moisturizer is formulated around Caffeine and Palmitoyl Tetrapeptide-7 to soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Lactobacillus/Cocoa Fruit Ferment Filtrate

Caffeine

Niacinamide

Persea Gratissima Oil

Prunus Armeniaca Kernel Oil

Squalane

Tocopheryl Acetate

Sodium Hyaluronate

Leuconostoc/Radish Root Ferment Filtrate

Sodium Acrylates Copolymer

Lecithin

Ethylhexylglycerin

Sodium Hydroxide

Phenoxyethanol

Water, Glycerin, Lactobacillus/Cocoa Fruit Ferment Filtrate, Caffeine, Niacinamide, Persea Gratissima Oil, Prunus Armeniaca Kernel Oil, Squalane, Tocopheryl Acetate, Sodium Hyaluronate, Leuconostoc/Radish Root Ferment Filtrate, Sodium Acrylates Copolymer, Lecithin, Ethylhexylglycerin, Sodium Hydroxide, Phenoxyethanol

Dicaprylyl Carbonate

Propanediol

Polyglyceryl-6 Distearate

Cetyl Alcohol

Glyceryl Behenate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Jojoba Esters

Albizia Julibrissin Bark Extract

Polyglyceryl-3 Beeswax

Phospholipids

Xanthan Gum

Glycine Soja Oil

Polysorbate 60

Sodium Phytate

Glycolipids

Sorbitan Isostearate

Butylene Glycol

Citric Acid

Glycine Soja Sterols

Hyaluronic Acid

Sodium Benzoate

Tocopherol

Carbomer

Darutoside

Sodium Lactate

Polysorbate 20

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Water, Glycerin, Dicaprylyl Carbonate, Propanediol, Polyglyceryl-6 Distearate, Cetyl Alcohol, Glyceryl Behenate, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Jojoba Esters, Albizia Julibrissin Bark Extract, Squalane, Caffeine, Polyglyceryl-3 Beeswax, Phospholipids, Ethylhexylglycerin, Xanthan Gum, Glycine Soja Oil, Polysorbate 60, Sodium Phytate, Glycolipids, Sorbitan Isostearate, Butylene Glycol, Citric Acid, Glycine Soja Sterols, Leuconostoc/Radish Root Ferment Filtrate, Hyaluronic Acid, Sodium Benzoate, Tocopherol, Carbomer, Darutoside, Sodium Lactate, Polysorbate 20, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1

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.

Caffeine is a naturally occurring plant compound found in coffee beans, tea leaves, cocoa pods, and guarana.

As an antioxidant, caffeine protects your skin from free radical damage caused by UV exposure and envionrmnetal stressors.

Early research also shows that caffeine can help calm redness, soothe irritated skin, and support hair growth by stimulating microcirculation in the scalp.

You might have seen eye creams marketing caffeine as a depuffing ingredient. This is because it is a vasoconstrictor meaning it can temporarily constrict blood vessels, though clinical evidence for this specific use is still limited.

Most skincare products contain this ingredient at concentrations between 1-6%. It is able to penetrate skin easily regardless of skin type or thickness.

Just so you know, a very small number of case reports describe caffeine-induced allergy. This ingredient is generally well-tolerated, non-irritating, and non-sensitizing for the majority of people.

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.

Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc. The trade name for this ingredient is Leucidal.

Leuconostoc comes from lactic acid.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

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.

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.

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. 02Caprylic/Capric Triglyceride
  3. 03Butylene Glycol
  4. 04Dicaprylyl Ether
  5. 05Siloxanetriol Alginate
  6. 06Caffeine
  7. 07Glyceryl Stearate
  8. 08PEG-100 Stearate
  9. 09Cetearyl Alcohol
  10. 10Cetearyl Olivate
  11. 11Sorbitan Olivate
  12. 12Lauryl Laurate
  13. 13Glycerin
  14. 14C14-22 Alcohols
  15. 15C12-20 Alkyl Glucoside
  16. 16Stearyl Dimethicone
  17. 17Octadecene
  18. 18Acrylates/C10-30 Alkyl Acrylate Crosspolymer
  19. 19Allantoin
  20. 20Disodium EDTA
Source · skinsort.com
02

Product index

Related product references

Product

cyrene Caffeine Eye Cream

cyrene Caffeine Eye Cream Ingredients in cyrene Caffeine Eye Cream explained: benefits, concerns, and detailed analysis of 29 ingredients including Water, Glycerin, and Dipropylheptyl Carbo…

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Product

the [pH]ix Caffeine Eye Cream

the [pH]ix Caffeine Eye Cream the [pH]ix Caffeine Eye Cream ingredients explained: Water, Aloe Barbadensis Leaf Juice, Propanediol, Persea Gratissima (Avocado) Oil, Butyrospermum Parkii (Sh…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side