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Skin science article

Allies of Skin 20% Vitamin C Brighten + Firm Serum Versus Drunk Elephant C-Firma Fresh Day Serum

Allies of Skin 20% Vitamin C Brighten + Firm Serum Versus Drunk Elephant C-Firma Fresh Day Serum This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Glutathione to brighten dull-looking skin. This brightening serum is formulated around Asco

Allies of Skin 20% Vitamin C Brighten + Firm Serum Versus Drunk Elephant C-Firma Fresh Day Serum

This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Glutathione to brighten dull-looking skin.

This brightening serum is formulated around Ascorbic Acid and Tocopherol to brighten dull-looking skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Propanediol

Glycerin

3-O-Ethyl Ascorbic Acid

Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane

Dimethyl Isosorbide

Helianthus Annuus Seed Wax

Polyglyceryl-10 Tristearate

Ethoxydiglycol

Dicaprylyl Ether

Water

Caprylyl Glycol

Citrus Aurantium Dulcis Callus Culture Extract

Glutathione

Acetyl Cysteine

Dimethylmethoxy Chromanol

Ergothioneine

Tocopherol

Gluconolactone

Leuconostoc/Radish Root Ferment Filtrate

Xanthan Gum

Silica

Sodium Benzoate

Calcium Gluconate

Phenoxyethanol

Propanediol, Glycerin, 3-O-Ethyl Ascorbic Acid, Benzimidazole Diamond Amidoethyl Urea Carbamoyl Propyl Polymethylsilsesquioxane, Dimethyl Isosorbide, Helianthus Annuus Seed Wax, Polyglyceryl-10 Tristearate, Ethoxydiglycol, Dicaprylyl Ether, Water, Caprylyl Glycol, Citrus Aurantium Dulcis Callus Culture Extract, Glutathione, Acetyl Cysteine, Dimethylmethoxy Chromanol, Ergothioneine, Tocopherol, Gluconolactone, Leuconostoc/Radish Root Ferment Filtrate, Xanthan Gum, Silica, Sodium Benzoate, Calcium Gluconate, Phenoxyethanol

Ascorbic Acid

Laureth-23

Lactobacillus/Pumpkin Ferment Extract

Sclerocarya Birrea Seed Oil

Dipotassium Glycyrrhizate

Glycyrrhiza Glabra Root Extract

Vitis Vinifera Juice Extract

Ferulic Acid

Phyllanthus Emblica Fruit Extract

Camellia Sinensis Leaf Extract

Lactobacillus/Punica Granatum Fruit Ferment Extract

Sodium Hyaluronate Crosspolymer

Sodium Hyaluronate

Oryza Sativa Bran Extract

Glutamylamidoethyl Imidazole

Tetrahydrobisdemethoxydiferuloylmethane

Tetrahydrodemethoxydiferuloylmethane

Tetrahydrodiferuloylmethane

Pentylene Glycol

Caprylhydroxamic Acid

Sorbic Acid

Chondrus Crispus Extract

Ethylhexylglycerin

Water, Dimethyl Isosorbide, Ascorbic Acid, Laureth-23, Glycerin, Tocopherol, Lactobacillus/Pumpkin Ferment Extract, Sclerocarya Birrea Seed Oil, Dipotassium Glycyrrhizate, Glycyrrhiza Glabra Root Extract, Vitis Vinifera Juice Extract, Ferulic Acid, Phyllanthus Emblica Fruit Extract, Camellia Sinensis Leaf Extract, Lactobacillus/Punica Granatum Fruit Ferment Extract, Propanediol, Gluconolactone, Sodium Hyaluronate Crosspolymer, Sodium Hyaluronate, Oryza Sativa Bran Extract, Glutamylamidoethyl Imidazole, Tetrahydrobisdemethoxydiferuloylmethane, Tetrahydrodemethoxydiferuloylmethane, Tetrahydrodiferuloylmethane, Pentylene Glycol, Caprylhydroxamic Acid, Leuconostoc/Radish Root Ferment Filtrate, Sorbic Acid, Phenoxyethanol, Sodium Benzoate, Caprylyl Glycol, Chondrus Crispus Extract, Ethylhexylglycerin

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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Dimethyl Isosorbide (often shortened to DMI) is a sugar-derived solvent made from sorbitol. It's used to dissolve tricky ingredients and help them mix smoothly into a formula.

Many actives sit as gritty crystals when undissolved, so DMI swoops in to full dissolve them. This helps improve texture, stability, and how evenly an active is distributed.

It does have a penetration-enhancing reputation that is a bit more nuanced than marketing suggests; a cell study on human skin found that 10% DMI didn't significantly boost the permeation of Hydroquinone, Salicylic Acid, or Octadecenedioic Acid compared to controls (though it did improve their solubility in the formula itself).

Typical usage concentrations usually range from 1-10% depending on the formula's needs; this ingredient is also well tolerated at these levels.

Gluconolactone is a PHA. PHAs are a great gentle alternative to traditional AHAs.

When applied, Gluconolactone has the same affect on skin as AHAs such as lactic acid. It helps dissolve the dead skin cells in the top layer of your skin. This improves texture and brightens the skin.

PHAs are more gentle than AHAs due to their larger structure. They do not penetrate as deeply as AHAs and take a longer time to dissolve dead cells. Studies show PHAs do not cause as much irritation.

Gluconolactone has some interesting properties:

In a 2004 study, Gluconolactone was found to prevent UV damage in mouse skin cells and has not been found to increase sun sensitivity. However, we still recommend wearing SPF daily.

This ingredient is is an created by reacting gluconic acid with an alcohol.

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.

Leuconostoc/Radish Root Ferment Filtrate is a natural preservative. It comes from fermenting radish roots with a bacteria called leuconostoc. The trade name for this ingredient is Leucidal.

Leuconostoc comes from lactic acid.

This ingredient has antimicrobial properties and helps prevent the growth of bacteria in a product.

Leuconostoc is used to make the traditional Korean side-dish, kimchi. It is also used to make sourdough bread (both incredibly yummy foods).

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.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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.

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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. 03Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  4. 04Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
  5. 05However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  6. 06Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
  7. 07In skincare formulas, citric acid can:
  8. 08While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  9. 09Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
  10. 10Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.
  11. 11However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's…
  12. 12Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  13. 13Topically, glycerin does several things at once:
  14. 14Your 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.
  15. 15Aquaporin-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.
  16. 16This 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.
  17. 17Just know very high concentrations (>40%) can feel tacky in low humidity.
  18. 18Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  19. 19Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.
  20. 20There are two forms of panthenol: D and L.
Source · skinsort.com
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