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The INKEY List Alpha Arbutin Serum Versus Niod Copper Amino Isolate Lipid 1% (CAIL)

The INKEY List Alpha Arbutin Serum Versus Niod Copper Amino Isolate Lipid 1% (CAIL) This brightening serum is formulated around Alpha-Arbutin to fade the look of dark spots and brighten dull-looking skin. This barrier-repair serum is formulated around Bisabolo

The INKEY List Alpha Arbutin Serum Versus Niod Copper Amino Isolate Lipid 1% (CAIL)

This brightening serum is formulated around Alpha-Arbutin to fade the look of dark spots and brighten dull-looking skin.

This barrier-repair serum is formulated around Bisabolol to strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Butylene Glycol

Propanediol

Glycerin

Alpha-Arbutin

Dicaprylyl Carbonate

Caprylic/Capric Triglyceride

Phenoxyethanol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Caprylyl Glycol

Squalane

Phospholipids

Glycine Soja Oil

Carbomer

Polysorbate 60

Sodium Phytate

Glycolipids

Sorbitan Isostearate

Leuconostoc/Radish Root Ferment Filtrate

Sodium Hydroxide

Glycine Soja Sterols

Hyaluronic Acid

Tocopherol

Water, Butylene Glycol, Propanediol, Glycerin, Alpha-Arbutin, Dicaprylyl Carbonate, Caprylic/Capric Triglyceride, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Caprylyl Glycol, Squalane, Phospholipids, Glycine Soja Oil, Carbomer, Polysorbate 60, Sodium Phytate, Glycolipids, Sorbitan Isostearate, Leuconostoc/Radish Root Ferment Filtrate, Sodium Hydroxide, Glycine Soja Sterols, Hyaluronic Acid, Tocopherol

Hydrogenated Starch Hydrolysate

Sucrose Laurate

Sucrose Stearate

Copper Tripeptide-1 Palmitamide

Hydroxymethoxyphenyl Propylmethylmethoxybenzofuran

Vetiveria Zizanoides Root Extract

Aphanizomenon Flos-Aquae Extract

Hydroxymethoxyphenyl Decanone

Bisabolol

Biosaccharide Gum-1

Maltodextrin

Potassium Sorbate

Sodium Benzoate

Chlorphenesin

Squalane, Caprylic/Capric Triglyceride, Glycerin, Water, Hydrogenated Starch Hydrolysate, Sucrose Laurate, Propanediol, Sucrose Stearate, Copper Tripeptide-1 Palmitamide, Glycolipids, Hydroxymethoxyphenyl Propylmethylmethoxybenzofuran, Vetiveria Zizanoides Root Extract, Aphanizomenon Flos-Aquae Extract, Hydroxymethoxyphenyl Decanone, Bisabolol, Biosaccharide Gum-1, Maltodextrin, Potassium Sorbate, Sodium Benzoate, Chlorphenesin, 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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

Glycolipids are natural, sustainable biosurfactants. They are both surfactants (cleansing agents) and emollients.

Made from lipids and sugars, in-vitro studies show glycolipids are a gentle alternative to conventional surfactants. They also possess foaming properties to give cleaning products a nice texture.

One manufacturer study found their glycolipid also demonstrated sebum reduction and helped reduced oiliness after four weeks. This means it can also be great for scalp care.

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.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

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!

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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. 03Cocamidopropyl Betaine is a fatty acid created by mixing similar compounds in coconut oil and dimethylaminopropylamine, a compound with two amino groups.
  4. 04This ingredient is a surfactant and cleanser. It helps gather the dirt, pollutants, and other impurities in your skin to be washed away. It also helps thicken a product and make the texture more creamy.
  5. 05Being created from coconut oil means Cocamidopropyl Betaine is hydrating for the skin.
  6. 06While Cocamidopropyl Betaine was believed to be an allergen, a study from 2012 disproved this. It found two compounds in unpure Cocamidopropyl Betaine to be the irritants: aminoamide and 3-dimethylaminopropylamine. High-grade and pure Cocamidopropyl…
  7. 07Peg-120 Methyl Glucose Dioleate is used to improve texture and stability of a product. It is sugar based and helps thicken a product.
  8. 08Once applied, it also creates a thin film to trap moisture in. This helps keep your skin hydrated.
  9. 09This ingredient is the polyethylene glycol ether of the diester of oleic acid and methylglucose. The 120 represents an average of 120 moles of ethylene oxide.
  10. 10There is limited research on this ingredient, although it is considered safe to use in skincare products.
  11. 11Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, …
  12. 12Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.
  13. 13Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.
  14. 14Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.
  15. 15It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.
  16. 16While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.
  17. 17If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.
  18. 18Chances are, you eat sodium chloride every day. Sodium Chloride is also known as table salt. This ingredient has many purposes in skincare: thickener, emulsifier, and exfoliator.
  19. 19You'll most likely find this ingredient in cleansers where it is used to create a gel-like texture. As an emulsifier, it also prevents ingredients from separating.
  20. 20You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.
Source · skinsort.com
02

Product index

Related product references

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03

Comparison edit

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