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Paula's Choice C15 Super Booster Versus The INKEY List Tranexamic Acid Night Treatment

Paula's Choice C15 Super Booster Versus The INKEY List Tranexamic Acid Night Treatment This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles. This brightening serum is formulate

Paula's Choice C15 Super Booster Versus The INKEY List Tranexamic Acid Night Treatment

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

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Butylene Glycol

Ascorbyl Glucoside

Tranexamic Acid

Euterpe Oleracea Fruit Extract

1-Methylhydantoin-2-Imide

Sodium Acrylates Copolymer

Carbomer

Cetearyl Olivate

Benzyl Alcohol

Sorbitan Olivate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Lecithin

Squalane

Ethylhexylglycerin

Sodium Gluconate

Polysorbate 60

Dehydroacetic Acid

Lactobacillus Ferment

Sorbitan Isostearate

Water, Butylene Glycol, Glycerin, Ascorbyl Glucoside, Tranexamic Acid, Euterpe Oleracea Fruit Extract, 1-Methylhydantoin-2-Imide, Sodium Acrylates Copolymer, Phenoxyethanol, Carbomer, Sodium Hydroxide, Cetearyl Olivate, Benzyl Alcohol, Sorbitan Olivate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Lecithin, Squalane, Ethylhexylglycerin, Sodium Gluconate, Polysorbate 60, Dehydroacetic Acid, Lactobacillus Ferment, Sorbitan Isostearate

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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.

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.

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!

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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

Paula's Choice Refreshing Moisture MistIngredients explained

  1. 01Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.
  2. 02It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  3. 03Expand to read more
  4. 04Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  5. 05One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
  6. 06Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.
  7. 07BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting…
  8. 08It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive.
  9. 09A derivative of Urea, that works as a strong moisturizer and humectant meaning that it helps the skin to cling onto water and thus to make it hydrated and elastic.
  10. 10According to manufacturer's data, Hydroxyethyl Urea has a similar moisturizing ability to glycerin (measured at 5%), but it feels nicer on the skin as it is non-sticky and non-tacky and gives a lubricous and moist feeling to the skin.
  11. 11A natural moisturizer that’s also in our skin
  12. 12A super common, safe, effective and cheap molecule used for more than 50 years
  13. 13Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  14. 14Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  15. 15High-glycerin moisturizers are awesome for treating severely dry skin
  16. 16We don't have description for this ingredient yet.
  17. 17Amino acids are important natural moisturizing factors (NMFs), that can be found naturally in the skin where they help the epidermis (upper layer of the skin) to stay nice and hydrated.
  18. 18Amino acids are also the building blocks of proteins, such as collagen, so when you thoroughly chop up a big collagen molecule, you end up with an amino acid mixture, like this guy we are writing about. Btw, if you chop it up less thoroughly, you ge…
  19. 19Amino acids have low molecular weight (about 150 Da), so they can penetrate the upper layer of the skin where they help moisture retention and enhance the skin's suppleness and flexibility. In hair care, Collagen Amino Acids are able to improve shin…
  20. 20It’s the - sodium form - cousin of the famous NMF, hyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here. The TL; DR version of HA is that it's a huge polymer (big molecule from repeated sub…
Source · incidecoder.com
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Comparison edit

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