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The INKEY List Polyglutamic Acid Dewy Sunscreen SPF 30 Versus The INKEY List Succinic Acid Acne Treatment

The INKEY List Polyglutamic Acid Dewy Sunscreen SPF 30 Versus The INKEY List Succinic Acid Acne Treatment This chemical sunscreen covers most of the UV range, lighter on the deep UVA that drives aging. This acne treatment is formulated around Colloidal Sulfur

The INKEY List Polyglutamic Acid Dewy Sunscreen SPF 30 Versus The INKEY List Succinic Acid Acne Treatment

This chemical sunscreen covers most of the UV range, lighter on the deep UVA that drives aging.

This acne treatment is formulated around Colloidal Sulfur and Salicylic Acid to clear breakouts and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Octocrylene

Glycerin

Ethylhexyl Salicylate

Coco-Caprylate/Caprate

Butyl Methoxydibenzoylmethane

Phenylbenzimidazole Sulfonic Acid

Triheptanoin

Saccharomyces Ferment

Cetearyl Alcohol

Glyceryl Stearate Se

Tromethamine

Glyceryl Caprylate

Propanediol

C9-12 Alkane

Dilinoleic Acid/Butanediol Copolymer

Sodium Stearoyl Glutamate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Dimethicone

Squalane

Hectorite

Lauroyl Lysine

Hydroxyethylcellulose

Caprylhydroxamic Acid

Dimethiconol

Polysorbate 60

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Oryza Sativa Hull Extract

Castor Oil/Ipdi Copolymer

Phenoxyethanol

Polyglutamic Acid

Sorbitan Isostearate

Camellia Sinensis Leaf Extract

Ipomoea Batatas Root Extract

Hydroxyacetophenone

Sodium Benzoate

1,2-Hexanediol

Caprylyl Glycol

Lactobacillus Ferment Lysate

Saccharomyces Lysate

Water, Octocrylene, Glycerin, Ethylhexyl Salicylate, Coco-Caprylate/Caprate, Butyl Methoxydibenzoylmethane, Phenylbenzimidazole Sulfonic Acid, Triheptanoin, Saccharomyces Ferment, Cetearyl Alcohol, Glyceryl Stearate Se, Tromethamine, Glyceryl Caprylate, Propanediol, C9-12 Alkane, Dilinoleic Acid/Butanediol Copolymer, Sodium Stearoyl Glutamate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Dimethicone, Squalane, Hectorite, Lauroyl Lysine, Hydroxyethylcellulose, Caprylhydroxamic Acid, Dimethiconol, Polysorbate 60, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Oryza Sativa Hull Extract, Castor Oil/Ipdi Copolymer, Phenoxyethanol, Polyglutamic Acid, Sorbitan Isostearate, Camellia Sinensis Leaf Extract, Ipomoea Batatas Root Extract, Hydroxyacetophenone, Sodium Benzoate, 1,2-Hexanediol, Caprylyl Glycol, Lactobacillus Ferment Lysate, Saccharomyces Lysate

Caprylic/Capric Triglyceride

Stearic Acid

Colloidal Sulfur

Succinic Acid

Salicylic Acid

Benzyl Alcohol

Sodium Hyaluronate

Ethylhexylglycerin

Sodium Hydroxide

Dehydroacetic Acid

Malachite Extract

Trisodium Ethylenediamine Disuccinate

CI 75810

Water, Caprylic/Capric Triglyceride, Glyceryl Stearate Se, Stearic Acid, Cetearyl Alcohol, Colloidal Sulfur, Glycerin, Succinic Acid, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Salicylic Acid, Phenoxyethanol, Squalane, Benzyl Alcohol, Sodium Hyaluronate, Polysorbate 60, Ethylhexylglycerin, Sodium Hydroxide, Dehydroacetic Acid, Malachite Extract, Sorbitan Isostearate, Trisodium Ethylenediamine Disuccinate, CI 75810

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.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

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.

Glyceryl Stearate Se is a self-emulsifying (SE) form of glyceryl stearate. Self-emusifying means this ingredient automatically blends with water. It is an emulsifier, emollient, and cleansing agent.

As an emulsifier, Glyceryl Stearate Se prevents ingredients such as oil and water from separating. It is also a surfactant, meaning it helps cleanse the skin. Surfactants help gather oil, dirt, and other pollutants so they may be rinsed away easily.

Emollients help your skin stay smooth and soft. It does so by creating a film on top of the skin that helps trap moisture in.

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.

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 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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  7. 07Topically, glycerin does several things at once:
  8. 08Your 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.
  9. 09Aquaporin-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.
  10. 10This 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.
  11. 11Just know very high concentrations (>40%) can feel tacky in low humidity.
  12. 12Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  13. 13Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.
  14. 14In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.
  15. 15Interestingly, the size of the molecule affects its behavior:
  16. 16Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.
  17. 17Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.
  18. 18You'll typically see concentrations between 0.1-2% for this ingredient.
  19. 19Water. 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.
  20. 20So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
Source · skinsort.com
02

Product index

Related product references

Product

The Inkey List Advanced Retinal Serum

The Inkey List Advanced Retinal Serum The Inkey List Advanced Retinal Serum ingredients explained: Aqua (Water), Glycerin, Caprylic/Capric Triglyceride, Dicaprylyl Carbonate, Polyglyceryl-6…

Source: incidecoder.comView reference →

Product

The Inkey List Polyglutamic Acid

The Inkey List Polyglutamic Acid The Inkey List Polyglutamic Acid ingredients explained: Aqua (Water), Dimethicone, Butylene Glycol, Bis-PEG-12 Dimethicone, Glycerin, Polymethylsilsesquioxa…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side