Peptide Skincare & BeautySkin science and ingredient guides

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The INKEY List Caffeine Eye Cream Versus The Saem Iceland Hydrating Eye Stick

The INKEY List Caffeine Eye Cream Versus The Saem Iceland Hydrating Eye Stick This anti-aging eye moisturizer is formulated around Caffeine and Palmitoyl Tetrapeptide-7 to soften the look of wrinkles. This anti-aging eye moisturizer is formulated around Xylito

The INKEY List Caffeine Eye Cream Versus The Saem Iceland Hydrating Eye Stick

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

This anti-aging eye moisturizer is formulated around Xylitol and Niacinamide to soften the look of wrinkles and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Alcohol

Sodium Stearate

Sodium Palmitate

PEG-12 Dimethicone

Xylitol

Niacinamide

PEG-8

Bis-PEG-18 Methyl Ether Dimethyl Silane

Dimethicone

Sodium Citrate

Potassium Alginate

Methyl Methacrylate Crosspolymer

Parfum

1,2-Hexanediol

Laminaria Japonica Extract

Cetraria Islandica Extract

Mesembryanthemum Crystallinum Extract

Adenosine

Zingiber Officinale Root Extract

Eugenia Caryophyllus Flower Extract

Polygonum Cuspidatum Root Extract

Zanthoxylum Piperitum Fruit Extract

Polyglutamic Acid

Glycolic Acid

Arginine

Carnosine

Glutathione

Acetyl Cysteine

Ascorbic Acid

Sh-Octapeptide-4

Water, Butylene Glycol, Alcohol, Sodium Stearate, Sodium Palmitate, PEG-12 Dimethicone, Xylitol, Glycerin, Niacinamide, PEG-8, Bis-PEG-18 Methyl Ether Dimethyl Silane, Dimethicone, Sodium Citrate, Potassium Alginate, Methyl Methacrylate Crosspolymer, Phenoxyethanol, Xanthan Gum, Parfum, 1,2-Hexanediol, Citric Acid, Laminaria Japonica Extract, Cetraria Islandica Extract, Mesembryanthemum Crystallinum Extract, Adenosine, Zingiber Officinale Root Extract, Eugenia Caryophyllus Flower Extract, Polygonum Cuspidatum Root Extract, Zanthoxylum Piperitum Fruit Extract, Polyglutamic Acid, Glycolic Acid, Arginine, Carnosine, Glutathione, Acetyl Cysteine, Ascorbic Acid, Sh-Octapeptide-4

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.

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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

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.

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.

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. 03Helianthus Annuus Seed Oil is a plant oil derived from the seeds of a sunflower.
  4. 04It is rich in fatty acids, primarily linoleic acid and oleic acid. This gives it emollient and skin conditioning properties.
  5. 05The reason this ingredient is so effective is because it forms a thin film on the skin that reduces transepidermal water loss (TEWL) while supplying linoleic acid to the stratum corneum to improve barrier strength.
  6. 06The high linoleic acid content is particularly noteworthy for acne-prone skin.
  7. 07Research suggests that acne-prone skin tends to be deficient in linoleic acid in sebum. Topical application may help replenish this to support a healthier follicular environment and less comedone-promoting sebum.
  8. 08One randomized study found sunflower seed oil preserved skin barrier integrity in adult volunteers with and without atopic dermatitis (outperforming olive oil).
  9. 09This ingredient is well-studied, gentle, and an effective emollient suitable for most skin types.
  10. 10On fungal acne: This ingredient may not be Fungal acne (Malassezia folliculitis) safe. This is because it contains fatty acids with carbon chain lengths in the C11-C24 range.
  11. 11Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  12. 12It 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.
  13. 13On 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.
  14. 14Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  15. 15You'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.
  16. 16Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  17. 17Safety-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.
  18. 18Adverse 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.
  19. 19Tocopherol is a fat-soluble antioxidant known as Vitamin E.
  20. 20You'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 damag…
Source · skinsort.com
02

Product index

Related product references

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03

Comparison edit

Read side by side