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Colibri Skincare Vitamin C 20 Booster Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum

Colibri Skincare Vitamin C 20 Booster Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Tetrahexyldecyl Ascorbate to brighten dull-looking skin and fade the look of dark spo

Colibri Skincare Vitamin C 20 Booster Versus Paula's Choice 25% Vitamin C + Glutathione Clinical Serum

This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Tetrahexyldecyl Ascorbate to brighten dull-looking skin and fade the look of dark spots.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

3-O-Ethyl Ascorbic Acid

Tetrahexyldecyl Ascorbate

3-Glyceryl Ascorbate

Glycerin

Pentylene Glycol

Propylheptyl Caprylate

Glyceryl Stearate Citrate

Coco-Caprylate/Caprate

Acetyl Zingerone

Hydrogenated Lecithin

Hexylresorcinol

Polyglyceryl-3 Stearate

Hydrogenated Phosphatidylcholine

Allantoin

Microcrystalline Cellulose

Sodium Stearoyl Glutamate

Cellulose Gum

Tocopherol

Citric Acid

Sodium Phytate

Xanthan Gum

Water, 3-O-Ethyl Ascorbic Acid, Tetrahexyldecyl Ascorbate, 3-Glyceryl Ascorbate, Glycerin, Pentylene Glycol, Propylheptyl Caprylate, Glyceryl Stearate Citrate, Coco-Caprylate/Caprate, Acetyl Zingerone, Hydrogenated Lecithin, Hexylresorcinol, Polyglyceryl-3 Stearate, Hydrogenated Phosphatidylcholine, Allantoin, Microcrystalline Cellulose, Sodium Stearoyl Glutamate, Cellulose Gum, Tocopherol, Citric Acid, Sodium Phytate, Xanthan Gum

Dimethicone

C9-12 Alkane

Ascorbyl Glucoside

Silica

Pyrus Malus Fruit Extract

Polyglyceryl-6 Polyricinoleate

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Oryza Sativa Bran Extract

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Cetyl Alcohol

Caprylyl Glycol

Lysine Carboxymethyl Cysteinate

Glutathione

Sodium Citrate

Hexylene Glycol

Ethylhexylglycerin

Helianthus Annuus Seed Extract

Urea

Mannitol

Caprylic/Capric Triglyceride

Sodium PCA

Rosmarinus Officinalis Leaf Extract

Polysorbate 60

Sorbitan Isostearate

Trehalose

Ascorbic Acid

Glucose

Vanilla Planifolia Fruit Extract

Polyquaternium-51

Ergothioneine

Triacetin

Sodium Hyaluronate

Phenoxyethanol

Water, Tetrahexyldecyl Ascorbate, Dimethicone, Glycerin, C9-12 Alkane, Ascorbyl Glucoside, Silica, Pyrus Malus Fruit Extract, Hydrogenated Lecithin, Polyglyceryl-6 Polyricinoleate, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Xanthan Gum, Oryza Sativa Bran Extract, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Cetyl Alcohol, Caprylyl Glycol, Lysine Carboxymethyl Cysteinate, Coco-Caprylate/Caprate, Tocopherol, Glutathione, Sodium Citrate, Sodium Phytate, Hexylene Glycol, Ethylhexylglycerin, Helianthus Annuus Seed Extract, Urea, Mannitol, Caprylic/Capric Triglyceride, Sodium PCA, Rosmarinus Officinalis Leaf Extract, Polysorbate 60, Sorbitan Isostearate, Trehalose, Ascorbic Acid, Glucose, Vanilla Planifolia Fruit Extract, Polyquaternium-51, Ergothioneine, Triacetin, Sodium Hyaluronate, Phenoxyethanol

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.

Coco-Caprylate/Caprate is a lightweight ester created from coconut oil fatty acids, caprylic acid, and capric acid.

It is an emollient that helps soften skin and reduce transepidermal water loss (TEWL). What sets it apart from heavier emollients is its ultralight, non-greasy feel.

Once applied, this ingredient dries down quickly and leaves a dry, silky finish behind. This also helps improve spreadability and texture.

This ingredient has an excellent safety-record and is non-irritating.

Typical concentrations for cosmetics range from 0.5-62%.

Research on Malassezia growth found no growth on fatty acid esters with chain lengths shorter than 12 carbons (it prefers C11-24).

Since Coco-Caprylate/Caprate is built on C8 and C10 fatty acids, it is out of the range that Malassezia metabolizes, and therefore safe for fungal acne.

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.

Hydrogenated Lecithin is a more stable version of lecithin.

It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.

This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.

Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.

Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.

A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).

Sodium Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.

Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.

Tetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.

THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).

Because it’s oil-soluble, THD dives deep into your skin’s fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) that mainly works on the surface.

Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when it’s stressed from pollution or sun.

Want to fade dark spots or tackle hyperpigmentation? You’ll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on stubborn discoloration, even in melasma-prone skin.

A note on THD: It’s has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).

While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.

THD is pretty stable, but it’s still vulnerable to degradation like ascorbic acid. Too much light or heat (above 113°F / 45°C) can break it down over time. Go for dark and opaque packaging that keeps it safe and shady!

Read more about other types of Vitamin C:

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!

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. 02Niacinamide
  3. 03Acetyl Glucosamine
  4. 04Ascorbyl Glucoside
  5. 05Butylene Glycol
  6. 06Phospholipids
  7. 07Sodium Hyaluronate
  8. 08Allantoin
  9. 09Boerhavia Diffusa Root Extract
  10. 10Glycerin
  11. 11Dipotassium Glycyrrhizate
  12. 12Glycyrrhiza Glabra Root Extract
  13. 13Ubiquinone
  14. 14Epigallocatechin Gallate
  15. 15Beta-Glucan
  16. 16Panthenol
  17. 17Carnosine
  18. 18Genistein
  19. 19Citric Acid
  20. 20Sodium Citrate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side