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The INKEY List C-50 Blemish Night Treatment Versus Paula's Choice C15 Super Booster

The INKEY List C-50 Blemish Night Treatment Versus Paula's Choice C15 Super Booster This acne treatment is formulated around Sodium Ascorbyl Phosphate and Salicylic Acid to clear breakouts and refine skin texture. This brightening serum is formulated around As

The INKEY List C-50 Blemish Night Treatment Versus Paula's Choice C15 Super Booster

This acne treatment is formulated around Sodium Ascorbyl Phosphate and Salicylic Acid to clear breakouts and refine skin texture.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propanediol

Sodium Ascorbyl Phosphate

Salicylic Acid

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Phenoxyethanol

Caprylyl/Capryl Glucoside

Xanthan Gum

Glycerin

Sodium Hydroxide

Madecassoside

Ethylhexylglycerin

Hydroxyacetophenone

Sodium Gluconate

Sodium Metabisulfite

Lecithin

Ascorbyl Palmitate

Nelumbo Nucifera Flower Extract

Nymphaea Coerulea Flower Extract

Tocopherol

Helianthus Annuus Seed Oil

Water, Propanediol, Sodium Ascorbyl Phosphate, Salicylic Acid, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Phenoxyethanol, Caprylyl/Capryl Glucoside, Xanthan Gum, Glycerin, Sodium Hydroxide, Madecassoside, Ethylhexylglycerin, Hydroxyacetophenone, Sodium Gluconate, Sodium Metabisulfite, Lecithin, Ascorbyl Palmitate, Nelumbo Nucifera Flower Extract, Nymphaea Coerulea Flower Extract, Tocopherol, Helianthus Annuus Seed Oil

Ascorbic Acid

Dipropylene Glycol

Ethoxydiglycol

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

Bisabolol

Ferulic Acid

Sodium Phytate

Decylene Glycol

1,2-Hexanediol

Sphingomonas Ferment Extract

Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, 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.

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.

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 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.

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.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Glycerin
  3. 03Prunus Armeniaca Kernel Oil
  4. 04Persea Gratissima Oil
  5. 05Caprylic/Capric Triglyceride
  6. 06Squalane
  7. 07Cetearyl Alcohol
  8. 08Glyceryl Stearate Se
  9. 09Retinol
  10. 10Phenoxyethanol
  11. 11Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
  12. 12Benzyl Alcohol
  13. 13Phospholipids
  14. 14Tocopherol
  15. 15Polyacrylate Crosspolymer-6
  16. 16Glycine Soja Oil
  17. 17Ethylhexylglycerin
  18. 18Glycolipids
  19. 19Dehydroacetic Acid
  20. 20Polysorbate 60
Source · skinsort.com
02

Product index

Related product references

Product

The Inkey List Multi-Biotic

The Inkey List Multi-Biotic The Inkey List Multi-Biotic ingredients explained: Water (Aqua/Eau), Inulin, Glycerin, Isoamyl Laurate, Propanediol, Squalane, Cetearyl Olivate, Sorbitan Olivate…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side