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The INKEY List 15% Vitamin C And EGF Serum Versus Dr Sam’s Flawless Brightly Serum

The INKEY List 15% Vitamin C And EGF Serum Versus Dr Sam’s Flawless Brightly Serum This brightening serum is formulated around Ascorbyl Glucoside to brighten dull-looking skin and fade the look of dark spots. This brightening serum is formulated around Azelaic

The INKEY List 15% Vitamin C And EGF Serum Versus Dr Sam’s Flawless Brightly Serum

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

This brightening serum is formulated around Azelaic Acid and Niacinamide to fade the look of dark spots 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

Azelaic Acid

Caprylic/Capric Triglyceride

Niacinamide

Dicaprylyl Carbonate

Cetearyl Alcohol

Glycerin

Glyceryl Stearate Se

Cetearyl Olivate

Bakuchiol

Sorbitan Olivate

Disodium EDTA

Water, Azelaic Acid, Caprylic/Capric Triglyceride, Niacinamide, Dicaprylyl Carbonate, Ascorbyl Glucoside, Cetearyl Alcohol, Glycerin, Glyceryl Stearate Se, Cetearyl Olivate, Bakuchiol, Sorbitan Olivate, Benzyl Alcohol, Xanthan Gum, Phenoxyethanol, Sodium Hydroxide, Disodium EDTA, Dehydroacetic Acid

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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.

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.

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.

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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. 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. 06Caffeine is a naturally occurring plant compound found in coffee beans, tea leaves, cocoa pods, and guarana.
  7. 07As an antioxidant, caffeine protects your skin from free radical damage caused by UV exposure and envionrmnetal stressors.
  8. 08Early research also shows that caffeine can help calm redness, soothe irritated skin, and support hair growth by stimulating microcirculation in the scalp.
  9. 09You might have seen eye creams marketing caffeine as a depuffing ingredient. This is because it is a vasoconstrictor meaning it can temporarily constrict blood vessels, though clinical evidence for this specific use is still limited.
  10. 10Most skincare products contain this ingredient at concentrations between 1-6%. It is able to penetrate skin easily regardless of skin type or thickness.
  11. 11Just so you know, a very small number of case reports describe caffeine-induced allergy. This ingredient is generally well-tolerated, non-irritating, and non-sensitizing for the majority of people.
  12. 12Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  13. 13The 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 …
  14. 14Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  15. 15Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  16. 16Topically, glycerin does several things at once:
  17. 17Your 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.
  18. 18Aquaporin-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.
  19. 19This 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.
  20. 20Just know very high concentrations (>40%) can feel tacky in low humidity.
Source · skinsort.com
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