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Emma S. Ultimate Eye Cream Versus The INKEY List Caffeine Eye Cream

Emma S. Ultimate Eye Cream Versus The INKEY List Caffeine Eye Cream This anti-aging eye moisturizer is formulated around Avena Sativa Kernel Oil and Hydrolyzed Hyaluronic Acid to soften the look of wrinkles and hydrate skin. This anti-aging eye moisturizer is

Emma S. Ultimate Eye Cream Versus The INKEY List Caffeine Eye Cream

This anti-aging eye moisturizer is formulated around Avena Sativa Kernel Oil and Hydrolyzed Hyaluronic Acid to soften the look of wrinkles and hydrate 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

Avena Sativa Kernel Oil

Canola Oil

Caprylyl Methicone

Squalane

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Phenoxyethanol

Synthetic Fluorphlogopite

Dimethicone

Hydrolyzed Hyaluronic Acid

Biosaccharide Gum-1

Hesperidin Methyl Chalcone

Steareth-20

Dipeptide-2

Palmitoyl Tetrapeptide-7

Potassium Sorbate

Tocopherol

Beta-Sitosterol

Glycine Soja Oil

Squalene

Polysorbate 60

Sorbitan Isostearate

Sodium Citrate

Citric Acid

Water, Glycerin, Avena Sativa Kernel Oil, Canola Oil, Caprylyl Methicone, Squalane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Phenoxyethanol, Synthetic Fluorphlogopite, Dimethicone, Hydrolyzed Hyaluronic Acid, Biosaccharide Gum-1, Hesperidin Methyl Chalcone, Steareth-20, Dipeptide-2, Palmitoyl Tetrapeptide-7, Potassium Sorbate, Tocopherol, Beta-Sitosterol, Glycine Soja Oil, Squalene, Polysorbate 60, Sorbitan Isostearate, Sodium Citrate, Citric Acid

Dicaprylyl Carbonate

Propanediol

Polyglyceryl-6 Distearate

Cetyl Alcohol

Glyceryl Behenate

Jojoba Esters

Albizia Julibrissin Bark Extract

Caffeine

Polyglyceryl-3 Beeswax

Phospholipids

Ethylhexylglycerin

Xanthan Gum

Sodium Phytate

Glycolipids

Butylene Glycol

Glycine Soja Sterols

Leuconostoc/Radish Root Ferment Filtrate

Hyaluronic Acid

Sodium Benzoate

Carbomer

Darutoside

Sodium Lactate

Polysorbate 20

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

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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.

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.

Glycine Soja Oil is a plant-derived oil from soybean seeds. Like other oils, it is rich in essential fatty acids (mostly linoleic and oleic) that support skin hydration and barrier function.

The fatty acids are able to integrate into the lipid matrix of the stratum corneum to help soften skin and reduce water loss.

On top of that, soybean oil is rich in vitamins like vitamin E, a potent antioxidant.

Research on soybean's active components also point to anti-inflammatory, collagen-stimulating, antioxidant activity, and protection against UV-induced oxidative damage.

Most of this research applies to the broader soybean plant and not just the oil fraction alone.

This ingredient may not be fungal acne safe due to the oleic acid content.

This is a synthetic polymer. It helps improve the texture of products by adding thickness and gel-like feel.

It is also an emulsifer, meaning it prevents ingredients such as oil and water from separating. It also helps evenly disperse other ingredients.

Palmitoyl Tetrapeptide-7 (formerly Palmitoyl Tetrapeptide-3) is a synthetic peptide. Its main job is to fight what researchers call "inflammaging".

"Inflammaging" is the slow, low-grade chronic inflammation that quietly breaks down collagen as we age.

This ingredient calms down a specific inflammation signal in your skin cells (called IL-6). When left unchecked, this signal triggers enzymes that break down collagen and elastin.

Clinical testing showed statistically significant improvements in:

Studies also found the more of this ingredient used, the more your skin produces Collagen I, fibronectin, and hyaluronic acid.

You'll likely see this ingredient paired with Palmitoyl Tripeptide-1 in the well-known Matrixyl 3000 complex for enhanced anti-aging effects.

A 3% concentration applied twice daily for two months showed meaningful skin rejuvenation results in clinical panels.

Fungal acne note: Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

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.

Polysorbate 60 is used to help stabilize products. It is a surfactant and emulsifier. These properties help keep ingredients together in a product. Surfactants help reduce surface tension between ingredients with different states, such as liquids and solids. Emulsifiers help prevent oils and waters from separating.

Polysorbate 60 is sorbitol-based and created from the ethoxylation of sorbitan. Ethoxylation is a chemical reaction used to add ethylene oxide. Sorbitan is a the dehydrated version of sorbitol, a sugar found in fruits.

In this case, the 60 comes from reacting 60 units of ethylene oxide with sorbitan.

Polysorbates are commonly used in medicine and foods.

Sorbitan Isostearate is an emulsifer. It is created from isostearic acid and sorbitol.

As an emulsifier, it keeps the water and oil ingredients from separating. This keeps formulas stable and smooth.

In a 24 hour occlusive patch test on 56 subjects, 10% sorbitan isostearate was completely non-irritating. Most formulas use less than 10%.

Because it's a fatty acid ester, it may not be fungal acne safe since the Malassezia yeast can utilize it as a nutrient source.

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.

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!

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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. 03Camellia Sinensis Leaf Extract (tea extract) is one of the most well-researched plant extracts in skincare with an impressive resume.
  4. 04Black tea, green tea, and oolong tea are all harvested from the Camellia Sinensis plant.
  5. 05Studies show green tea extract and its catechins (like epigallocatechin gallate (EGCG)) help your skin cells product energy more efficiently and reducing the number of free-radicals that can damage your skin from the inside.
  6. 06In lab-grown skin models, this translated to younger, healthier, and stronger skin.
  7. 07There's also good sun protection data; researchers saw less DNA damage and redness on human skin when green tea was applied before UVB exposure. And the more they applied, the better the protection.
  8. 08Needless to say, this ingredient shouldn't replace your sunscreen. But it is a great supportive ingredient that you can already find in many sunscreens and antioxidant serums.
  9. 09A 2009 study found a 2% green tea lotion was effective for mild-to-moderate acne thanks to its anti-inflammatory and mild antimicrobial activity.
  10. 10The quality of the extract matters a lot here:
  11. 11Good extracts contain 50-90% catechins while lower quality ones are mostly there for marketing. We recommend reaching out to the brand if you have questions about the quality or source of their ingredients.
  12. 12Human Repeated Insult Patch Testing showed no irritation or sensitization at use concentrations (0.86% in leave-on products and up to 30% as leaf water).
  13. 13Tocopherol is a fat-soluble antioxidant known as Vitamin E.
  14. 14You'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…
  15. 15Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.
  16. 16It 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.
  17. 17This 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.
  18. 18This 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.
  19. 19In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.
  20. 20Concentrations usually range from 0.1-1% in most leave-on products.
Source · skinsort.com
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Product index

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Comparison edit

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