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The INKEY List Ceramide Serum Versus The INKEY List Tranexamic Acid Night Treatment

The INKEY List Ceramide Serum Versus The INKEY List Tranexamic Acid Night Treatment This barrier-repair treatment is formulated around Sodium Hyaluronate and Ceramide NP to strengthen the skin barrier and hydrate skin. This brightening serum is formulated arou

The INKEY List Ceramide Serum Versus The INKEY List Tranexamic Acid Night Treatment

This barrier-repair treatment is formulated around Sodium Hyaluronate and Ceramide NP to strengthen the skin barrier and hydrate skin.

This brightening serum is formulated around Ascorbyl Glucoside and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Butylene Glycol

Glycerin

Sodium Hyaluronate

Simmondsia Chinensis Seed Oil

Carbomer

Phenoxyethanol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Benzyl Alcohol

Squalane

Sodium Lauroyl Lactylate

Sodium PCA

Sodium Hydroxide

Sodium Stearoyl Glutamate

Sodium Lactate

Arginine

Aspartic Acid

Ethylhexylglycerin

Sodium Gluconate

PCA

Polysorbate 60

Dehydroacetic Acid

Ceramide NP

Glycine

Alanine

Sorbitan Isostearate

Ceramide AP

Phytosphingosine

Serine

Cholesterol

Valine

Xanthan Gum

Isoleucine

Proline

Threonine

Histidine

Phenylalanine

Ceramide EOP

Water, Butylene Glycol, Glycerin, Sodium Hyaluronate, Simmondsia Chinensis Seed Oil, Carbomer, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Benzyl Alcohol, Squalane, Sodium Lauroyl Lactylate, Sodium PCA, Sodium Hydroxide, Sodium Stearoyl Glutamate, Sodium Lactate, Arginine, Aspartic Acid, Ethylhexylglycerin, Sodium Gluconate, PCA, Polysorbate 60, Dehydroacetic Acid, Ceramide NP, Glycine, Alanine, Sorbitan Isostearate, Ceramide AP, Phytosphingosine, Serine, Cholesterol, Valine, Xanthan Gum, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Ceramide EOP

Ascorbyl Glucoside

Tranexamic Acid

Euterpe Oleracea Fruit Extract

1-Methylhydantoin-2-Imide

Sodium Acrylates Copolymer

Cetearyl Olivate

Sorbitan Olivate

Lecithin

Lactobacillus Ferment

Water, Butylene Glycol, Glycerin, Ascorbyl Glucoside, Tranexamic Acid, Euterpe Oleracea Fruit Extract, 1-Methylhydantoin-2-Imide, Sodium Acrylates Copolymer, Phenoxyethanol, Carbomer, Sodium Hydroxide, Cetearyl Olivate, Benzyl Alcohol, Sorbitan Olivate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Lecithin, Squalane, Ethylhexylglycerin, Sodium Gluconate, Polysorbate 60, Dehydroacetic Acid, Lactobacillus Ferment, Sorbitan Isostearate

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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.

Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.

This ingredient has been deemed safe for use in cosmetic formulations at concentrations up to 5%, and up to 10% in hair dyes. You'll typically see 0.5-2% in most rinse-off or leave-on products.

As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.

The sensitization picture is actually quite assuring as well:of nearly 71,000 patients patch tested with benzyl alcohol, only 0.21% showed a positive reaction with most of them being weakly positive.

This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.

It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.

Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.

At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.

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.

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

Dehydroacetic Acid is a synthetic preservative that keeps your products safe from microbes.

As an organic acid, it penetrates microbial cell walls and disrupts cellular metabolism. This makes it effective against bacteria, yeast, and mold.

It is effective at low concentrations (<0.6%). Clinical studies have found it to be non-irritating, non-sensitizing, and non-photosensitizing.

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.

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.

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.

This is the synthetic salt of gluconic acid, a form of PHA and mild exfoliant.

It is mainly used to stabilize oil and butter formulations from going bad. Sodium gluconate is a humectant, pH regulator, and chelating agent.

Chelating agents help neutralize unwanted metals from affecting the formulation.

Sodium gluconate is water-soluble.

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.

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.

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. 02Glycerin
  3. 03Coco-Glucoside
  4. 04Betaine
  5. 05Cetearyl Alcohol
  6. 06Stearic Acid
  7. 07Phenoxyethanol
  8. 08Benzyl Alcohol
  9. 09Xanthan Gum
  10. 10Acrylates/C10-30 Alkyl Acrylate Crosspolymer
  11. 11Inulin
  12. 12Ethylhexylglycerin
  13. 13Sodium Hydroxide
  14. 14Dehydroacetic Acid
  15. 15Polyquaternium-10
  16. 16Trisodium Ethylenediamine Disuccinate
  17. 17Hydrolyzed Sodium Hyaluronate
  18. 18Sodium Hyaluronate
  19. 19Lecithin
  20. 20Water, Glycerin, Coco-Glucoside, Betaine, Cetearyl Alcohol, Stearic Acid, Phenoxyethanol, Benzyl Alcohol, Xanthan Gum, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Inulin, Ethylhexylglycerin, Sodium Hydroxide, Dehydroacetic Acid, Polyquaternium-10,…
Source · skinsort.com
02

Product index

Related product references

Product

The Inkey List Brighten-i Eye Cream

The Inkey List Brighten-i Eye Cream The Inkey List Brighten-i Eye Cream ingredients explained: Water (Aqua/Eau), Dimethicone, Coco-Caprylate/Caprate, Glycerin, Caprylic/Capric Triglyceride,…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side