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The INKEY List 15% Vitamin C And EGF Serum Versus This Works Morning Expert Hyaluronic Serum

The INKEY List 15% Vitamin C And EGF Serum Versus This Works Morning Expert Hyaluronic Serum This brightening serum is formulated around Ascorbyl Glucoside to brighten dull-looking skin and fade the look of dark spots. This hydrating serum is formulated around

The INKEY List 15% Vitamin C And EGF Serum Versus This Works Morning Expert Hyaluronic Serum

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

This hydrating serum is formulated around Ascorbyl Glucoside and Sodium Hyaluronate to hydrate skin and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Ascorbyl Glucoside

Sodium Hydroxide

PEG-40 Hydrogenated Castor Oil

Phenoxyethanol

Benzyl Alcohol

Butylene Glycol

Xanthan Gum

Ethylhexylglycerin

Sodium Metabisulfite

Dehydroacetic Acid

Phytic Acid

Oligopeptide-1

Water, Ascorbyl Glucoside, Sodium Hydroxide, PEG-40 Hydrogenated Castor Oil, Phenoxyethanol, Benzyl Alcohol, Butylene Glycol, Xanthan Gum, Ethylhexylglycerin, Sodium Metabisulfite, Dehydroacetic Acid, Phytic Acid, Oligopeptide-1

Glycerin

Sodium Hyaluronate

Albizia Julibrissin Bark Extract

Heptyl Glucoside

Sodium Levulinate

Marrubium Vulgare Extract

Sodium Anisate

Parfum

Linalool

Heptanol

Sodium Benzoate

Citric Acid

Limonene

Water, Glycerin, Ascorbyl Glucoside, Sodium Hyaluronate, Albizia Julibrissin Bark Extract, Heptyl Glucoside, PEG-40 Hydrogenated Castor Oil, Phenoxyethanol, Sodium Levulinate, Benzyl Alcohol, Marrubium Vulgare Extract, Sodium Anisate, Xanthan Gum, Sodium Hydroxide, Phytic Acid, Ethylhexylglycerin, Parfum, Dehydroacetic Acid, Linalool, Heptanol, Sodium Benzoate, Citric Acid, Limonene

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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.

Ascorbyl Glucoside (AA-2G) is one of the most stable vitamin C derivatives out there.

It's made by attaching a glucose molecule to ascorbic acid; this glucose "cap" shields the vitamin C from air, light, heat, and metal ions that normally cause pure ascorbic acid to oxidize.

Once on your skin, the enzyme alpha-glucosidase snips off the glucose and gradually releases active ascorbic acid right where it's needed. Basically, it behaves like a slow-release pro-vitamin C with less of a stinging that high-strength ascorbic acid can cause.

The research supports the classic vitamin C benefits as well. In lab and human studies, AA-2G slowed down the skin's production of melanin (the pigment behind dark spots) and helped shield skin cells against sun damage better than ascorbyl phosphate.

These studies also showed AA-2G released vitamin C over a longer period.

A frequently cited manufacturer trial found that a 2% AA-2G face cream significantly improved wrinkle depth and skin roughness after 45 days.

And in 2009, a clinical trial showed it meaningfully lightened dark patches on the gums compared to a placebo.

There's also collagen-synthesis support (since vitamin C is a required cofactor for that) and an antioxidant effect too.

Typical usage is usually between 0.5-5% and most studies/products land around 2%.

AA-2G performs best when formulated at a mildly acidic pH (~5-7) which is much gentler than the pH that pure vitamin C demands (~2.5-3.5).

Just one thing worth knowing: the in-skin conversation rate is only about 55-60% by weight. So a 5% AA-2G product delivers roughly 2.75-3% of actual active vitamin C. On top of that, skin absorption is relatively low because the ingredient is water-soluble.

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.

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.

PEG-40 Hydrogenated Castor Oil is an emulsifier derived from castor oil.

As an emulsifying agent, it helps other ingredients like fragrances and fat-soluble vitamins dissolve cohesively.

Due to its large molecule size, it doesn't penetrate beyond the skin's surface.

This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.

A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.

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.

Phytic Acid is a gentle AHA and antioxidant. AHAs are chemical exfoliants that help remove dead skin cells. Phytic Acid has a slight and mild exfoliating effect.

The chemical makeup makes it classified as an AHA, much like lactic acid.

In some cases, it is a chelating agent. Chelating agents help prevent metals from binding to water, helping to stabilize the ingredients in a product.

An interesting fact about phytic acid is that it is considered an antinutrient. People do not have the enzyme needed to properly breakdown and digest phytic acid. When ingested, phytic acid binds to minerals and prevents them from being absorbed.

Read more about some other popular AHA's here:

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.

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 Side-by-side

  1. 01Water
  2. 02Dicaprylyl Carbonate
  3. 03Glycerin
  4. 04Niacinamide
  5. 05Propanediol
  6. 06Betaine
  7. 07Polyglyceryl-4 Isostearate
  8. 08Coco-Caprylate/Caprate
  9. 09Magnesium Sulfate
  10. 10Glycosphingolipids
  11. 11Glycolipids
  12. 12Sodium Benzoate
  13. 13Disteardimonium Hectorite
  14. 14Oleic Acid
  15. 15Potassium Sorbate
  16. 16Citric Acid
  17. 17Polyglycerin-3
  18. 18Water, Dicaprylyl Carbonate, Glycerin, Niacinamide, Propanediol, Betaine, Polyglyceryl-4 Isostearate, Coco-Caprylate/Caprate, Magnesium Sulfate, Glycosphingolipids, Glycolipids, Sodium Benzoate, Disteardimonium Hectorite, Oleic Acid, Potassium Sorba…
  19. 19Helianthus Annuus Seed Oil
  20. 20Alcohol
Source · skinsort.com
02

Product index

Related product references

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The Inkey List Squalane Oil

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The Inkey List Q10 Serum The Inkey List Q10 Serum ingredients explained: Water (Aqua/Eau), Propanediol, Butylene Glycol, Glycerin, Dicaprylyl Carbonate, Dimethicone, Caprylic/Capric Triglyc…

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03

Comparison edit

Read side by side